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Science is challenging because we do not know what we do not know. Commercial chemicals are often marketed with >99% purity, but 0.5-1% impurity can impact results and cloud data interpretation. We recently developed an assay for farnesol and aromatic fusel alcohols from Candida albicans . During proof-of-concept experiments using RPMI-1640 growth media, the buffering compound was switched from MOPS obtained from Acros Organics to MOPS obtained from Sigma-Aldrich, both labeled 99% + purity. We observed a twofold decrease in growth, along with a three- to fivefold increase in farnesol production per cell upon the switch. ICP-MS showed that trace Mn(II) was present in Acros MOPS but absent in Sigma MOPS. Optimal growth was achieved by the addition of Mn(II), Zn(II), and Fe(II). We established upper and lower limits for Fe(II), Zn(II), Cu(II), and Mn(II) that allowed similar growth and then assessed 16 different mineral combinations in RPMI-1640 base media. The results show an increased production of farnesol and the aromatic fusel alcohols when Zn(II) is abundant, and a further increase in the aromatic fusel alcohols when both Fe(II) and Zn(II) are abundant. Finally, antifungal susceptibility testing displayed no significant difference between RPMI/MOPS with and without mineral supplementation. Supplemental Mn(II) was most needed for cell growth, while supplemental Zn(II) was most needed for the production of farnesol and the aromatic fusel alcohols. To avoid these artifacts due to metal contamination, we now use a modified RPMI supplemented with 1 mg/ L of Cu(II), Zn(II), Mn(II), and Fe(II)., Importance: The dimorphic fungus Candida albicans is a major opportunistic pathogen of humans. RPMI-1640 is a chemically defined growth medium commonly used with C. albicans . We identified over 32,000 publications with keywords RPMI and C. albicans . Additionally, Antifungal Susceptibility Testing (AFST) protocols in the United States (CLSI) and Europe (EUCAST) utilize RPMI as a base media to assess drug efficacy against clinical fungal isolates. RPMI contains many nutrients but no added trace metals. We found that the growth characteristics with RPMI were dependent on which MOPS buffer was chosen and the contamination of that buffer by trace levels of Mn(II) and Zn(II). Added Mn(II) was most needed for cell growth while added Zn(II) was most needed for secretion of farnesol and other signaling molecules., Competing Interests: The authors declare no conflict of interest.

Ethnic identity is theorized to be a critical aspect of human development and is shown to be associated with health and well-being. The Ethnic Identity Scale is a widely used measure that assesses key aspects of ethnic identity development (Umaña-Taylor et al., 2004). The Multicultural Identity Integration Scale (MULTIIS) is a measure that has been more recently developed to assess key aspects of identity integration for individuals with multicultural identities (Yampolsky et al., 2016). Despite the ongoing utilization of these instruments, a comprehensive psychometric evaluation within Multiracial populations has yet to be established in extant literature. Addressing this gap, the present study aims to examine the internal consistency, factor structure, and other psychometric characteristics of the Ethnic Identity Scale and MULTIIS within a sample of 1,012 Multiracial adults in the United States. The majority of the sample identified as female (67.5%, n = 683), straight (80.1%, n = 798), having attained less than a college degree (62.3%, n = 627), and having a household income less than $60,000 (57.4%, n = 552). The majority of participants (55%, n = 557) were classified as having White and non-White racial/ethnic backgrounds, 45.0% ( n = 455) as non-White. Findings suggest the Ethnic Identity Scale fits the data poorly by all measures, despite supporting the three-factor structure recommended in the original study; the MULTIIS fits the data acceptably by all measures and supports both a three-factor first-order and eight-factor second-order structure recommended in the original study. Analyses of the MULTIIS three-factor first-order model's measurement invariance across race, gender, educational attainment, and household income identified variance for specific latent factors. Overall, the MULTIIS performed acceptably; however, studies relying on the MULTIIS should account for differential measurement. Implications for clinical, scientific, and public health practice are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Farnesol salvage, a two-step pathway converting farnesol to farnesyl pyrophosphate (FPP), occurs in bacteria, plants, and animals. This paper investigates the presence of this pathway in fungi. Through bioinformatics, biochemistry, and physiological analyses, we demonstrate its absence in the yeasts Saccharomyces cerevisiae and Candida albicans , suggesting a likely absence across fungi. We screened 1,053 fungal genomes, including 34 from C. albicans , for potential homologs to four genes ( Arabidopsis thaliana AtFOLK , AtVTE5 , AtVTE6 , and Plasmodium falciparum PfPOLK ) known to accomplish farnesol/prenol salvage in other organisms. Additionally, we showed that 3 H-farnesol was not converted to FPP or any other phosphorylated prenol, and exogenous farnesol was not metabolized within 90 minutes at any phase of growth and did not rescue cells from the toxic effects of atorvastatin, but it did elevate the levels of intracellular farnesol (F i ). All these experiments were conducted with C. albicans . In sum, we found no evidence for farnesol salvage in fungi., Importance: The absence of farnesol salvage constitutes a major difference in the metabolic capabilities of fungi. In terms of fungal physiology, the lack of farnesol salvage pathways relates to how farnesol acts as a quorum-sensing molecule in Candida albicans and why farnesol should be investigated for use in combination with other known antifungal antibiotics. Its absence is essential for a model (K. W. Nickerson et al., Microbiol Mol Biol Rev 88:e00081-22, 2024), wherein protein farnesylation, protein chaperones, and the unfolded protein response are combined under the unifying umbrella of a cell's intracellular farnesol (F i ). In terms of human health, farnesol should have at least two different modes of action depending on whether those cells have farnesol salvage. Because animals have farnesol salvage, we can now see the importance of dietary prenols as well as the potential importance of farnesol in treating neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and multiple sclerosis., Competing Interests: The authors declare no conflict of interest.

Objectives: Collective minoritized identities such as Black, Indigenous, and People of Color (BIPOC) may promote cross-racial solidarity. However, Asian Americans occupy a racially triangulated position as the "buffer minority" stereotyped as both the model minority and perpetual foreigner, complicating their inclusion in the BIPOC identity. The present study examined how the model minority and perpetual foreigner stereotypes relate to Asian Americans' perceived belongingness and identification with the BIPOC identity and, in turn, their interracial solidarity toward Black Americans., Method: A path analysis was conducted using cross-sectional data from a sample of 312 Asian Americans ( M age = 41.19, 69.87% college graduates, 46.79% foreign-born) to examine direct and indirect effects on Black community activism orientation (BCAO), with internalized model minority stereotype (MMS) and experiences of COVID-19 racial bias (CVRB) as exogenous predictors and perceived BIPOC inclusion and BIPOC self-identification as mediators., Results: The BIPOC variables demonstrated a direct and positive association with BCAO. Furthermore, internalized MMS negatively related to BCAO through the sum effect of decreased perceived BIPOC inclusion and BIPOC self-identification, while experiences of CVRB positively related to BCAO through the sum effect of increased perceived BIPOC inclusion and BIPOC self-identification., Conclusions: Asian Americans' perceived BIPOC inclusion and BIPOC self-identification are shaped by their racially triangulated position, characterized by both the inhibiting effect of internalized MMS and the promoting effect of experiences of CVRB. This heightened or diminished BIPOC self-concept subsequently influenced their willingness to engage in interracial solidarity for Black Americans. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

SUMMARYFarnesol was first identified as a quorum-sensing molecule, which blocked the yeast to hyphal transition in Candida albicans , 22 years ago. However, its interactions with Candida biology are surprisingly complex. Exogenous (secreted or supplied) farnesol can also act as a virulence factor during pathogenesis and as a fungicidal agent triggering apoptosis in other competing fungi. Farnesol synthesis is turned off both during anaerobic growth and in opaque cells. Distinctly different cellular responses are observed as exogenous farnesol levels are increased from 0.1 to 100 µM. Reported changes include altered morphology, stress response, pathogenicity, antibiotic sensitivity/resistance, and even cell lysis. Throughout, there has been a dearth of mechanisms associated with these observations, in part due to the absence of accurate measurement of intracellular farnesol levels ( F i ). This obstacle has recently been overcome, and the above phenomena can now be viewed in terms of changing F i levels and the percentage of farnesol secreted. Critically, two aspects of isoprenoid metabolism present in higher organisms are absent in C. albicans and likely in other yeasts. These are pathways for farnesol salvage (converting farnesol to farnesyl pyrophosphate) and farnesylcysteine cleavage, a necessary step in the turnover of farnesylated proteins. Together, these developments suggest a unifying model, whereby high, threshold levels of F i regulate which target proteins are farnesylated or the extent to which they are farnesylated. Thus, we suggest that the diversity of cellular responses to farnesol reflects the diversity of the proteins that are or are not farnesylated., Competing Interests: The authors declare no conflict of interest.

Background: Suicide and PTSD are pressing public health issues in the US, with discrimination and potentially traumatic experiences (PTEs) influencing mental health. However, the unique effects of these factors on Multiracial/ethnic adults' PTSD and suicidal thoughts/behaviors (STB) are not thoroughly researched., Methods: Using a cross-sectional design, an online survey was conducted (N = 1012) from October to December 2022. Multivariable logistic regression models analyzed relationships between PTEs, discriminatory events, and mental health outcomes, accounting for sociodemographics., Results: After adjusting for demographics, exposure to PTEs and discrimination correlated with heightened odds of PTSD and STB. Individual lifetime discrimination experiences and specific PTEs demonstrated varying associations with STB and PTSD. The study underscores discrimination's relevance as a risk factor., Limitations: The study's cross-sectional nature restricts causality or temporality interpretations. Moreover, the convenience sample of English-speaking online participants might not be reflective of all Multiracial/ethnic US adults., Conclusions: Findings underscore PTEs and discrimination's interconnectedness in Multiracial/ethnic mental health outcomes. Discrimination might pose similar risks to PTEs. Acknowledging discrimination as potential precursors for PTSD and STB aids accurate diagnosis and effective treatment planning. Incorporating racial/ethnic discrimination and traumatic experiences into PTSD conceptualization and assessment is pivotal. This knowledge informs tailored interventions and mental health education for this population., Competing Interests: Declaration of competing interest None., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Multiracial individuals are exposed to many forms of interpersonal racial discrimination, including general discrimination against their monoracial groups and discrimination against being multiracial. Because their families include members of different racial groups, multiracial people may also be exposed to various forms of discrimination from within the family. In the present study, we leverage recent advances in latent profile analysis to identify distinct patterns of family-based and external (i.e., from outside the family unit) discrimination experienced by multiracial college students, the differential impacts of these discrimination patterns on depressive and anxiety symptoms, and whether parental support of participants' multiracial experiences and identity impacts their exposure to different forms of discrimination. In a sample of 635 diverse multiracial college students ( M age = 21.2, SD = 5.3, range = 18-57, 74.0% female) from three U.S. universities, we identified three distinct discrimination profiles: High External and Familial Discrimination (43.2%) , Average External Low Familial Discrimination (32.1%) , and Low External and Familial Discrimination (24.7%). Profiles differed in depressive and anxiety symptomatology, with those in the High External and Familial Discrimination profile displaying the worst outcomes. Parental support of multiracial experiences was associated with lower levels of family-based discrimination. The complex relations between parental support, family-based discrimination, and multiracial participants' internalizing symptomology are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Candida albi c ans is a lifelong member of the mycobiome causing mucosal candidiasis and life-threatening, systemic, and intra-abdominal disease in immunocompromised and transplant patients. Despite the clinical importance of intra-abdominal candidiasis with mortality rates between 40% and 70%, the contribution of fungal virulence factors and host immune responses to disease has not been extensively studied. Secretion of the quorum-sensing molecule, farnesol, acts as a virulence factor for C. albicans during systemic infection, while inducing local, protective innate immune responses in oral models of infection. Previously, we reported that farnesol recruits macrophages to the peritoneal cavity in mice, suggesting a role for farnesol in innate immune responses. Here, we expand on our initial findings, showing that farnesol profoundly alters the peritoneal cavity microenvironment promoting innate inflammation. Intra-peritoneal injection of farnesol stimulates rapid local death of resident peritoneal cells followed by recruitment of neutrophils and inflammatory macrophages into the peritoneal cavity and peritoneal mesothelium associated with an early increase in chemokines followed by proinflammatory cytokines. These rapid inflammatory responses to farnesol significantly increase morbidity and mortality of mice with intra-abdominal candidiasis associated with increased formation of peritoneal adhesions, despite similar rates of fungal clearance from the peritoneal cavity and retro-peritoneal organs. C. albicans ddp3Δ/ddp3Δ knockout and reconstituted strains recapitulate these findings. This indicates that farnesol may be detrimental to the host during intra-abdominal infections. Importantly, our results highlight a need to understand how C. albicans virulence factors modulate the host immune response within the peritoneum, an exceedingly common site of Candida infection., Competing Interests: The authors declare no conflict of interest.

Introduction: Although research on racial-ethnic socialization with Asian American families examines academic and psychological outcomes, less is known about whether messages from mothers and fathers are related to their adolescent's Asian American sociopolitical values and family cohesion., Methods: Cross-sectional survey data were collected from 308 Asian American adolescents, ages 14-18, in the United States in 2021 (M age  = 16.83; standard deviation = 1.15)., Results: Using latent profile analysis, we found that there were three socialization profiles for mothers (integration socialization, moderate separation socialization, and high separation socialization) and two for fathers (integration socialization and high separation socialization). The integration socialization reported more maintenance of heritage culture and becoming American messages, with the lowest reports of awareness of discrimination and avoidance of outgroups. The high separation profile had the highest amount of maintenance of heritage culture messages, awareness of discrimination, and avoidance of outgroups but lowest amount of becoming American messages. Looking at profiles for youths' perceptions of mothers, the moderate separation profile had slightly lower scores on maintenance of heritage culture messages, moderate scores on avoidance of outgroups, and higher reports of becoming American and awareness of discrimination compared to the high separation profile. Adolescents with mothers in the integration profile had the greatest mother-child cohesion and highest level of sociopolitical values. With fathers, Asian American adolescents reported greater father-child cohesion in the integration profile, but there were no differences between socialization profiles and youth's Asian American sociopolitical values., Conclusions: Findings highlight the importance of parental messages on both identity outcomes (i.e., sociopolitical values) and family processes (i.e., family cohesion)., (© 2023 The Authors. Journal of Adolescence published by Wiley Periodicals LLC on behalf of Foundation for Professionals in Services to Adolescents.)

To date, psychosocial and interpersonal protective factors such as family connectedness have received little attention in studies of eating behaviors among sexual minority Asian Americans. Therefore, we investigated associations of family connectedness and two types of eating behavior regulation motives and the moderating role of individualism in these associations among 134 sexual minority Asian American young adults. Linear regression models assessed the main and interaction effects of family connectedness and individualism on introjected and identified eating behavior regulation motives. We observed a significant interaction effect between family connectedness and individualism only on introjected regulation. For participants with low levels of individualism, those who reported high levels of family connectedness had lower scores for introjected regulation of eating behavior. The findings of this study highlight the importance of examining strengths related to sexual minority Asian Americans by demonstrating the important role family connectedness plays in eating behavior regulation motives, particularly for those with lower individualism., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Aims: Farnesol was identified 20 years ago in a search for Candida albicans quorum sensing molecules (QSM), but there is still uncertainty regarding many aspects of its mode of action including whether it employs farnesol transport mechanisms other than diffusion. Based on the structural similarity between farnesol and the farnesylated portion of the MTL a pheromone, we explored the effects of ploidy and mating type locus ( MTL ) on the antifungal activity of exogenous farnesol. Methods and results: We approached this question by examining five MTL a and five MTLα haploid strains with regard to their farnesol sensitivity in comparison to six heterozygous MTL a / α diploids. We examined the haploid and diploid strains for percent cell death after exposure of exponentially growing cells to 0-200 µM farnesol. The heterozygous ( MTL a /α) diploids were tolerant of exogenous farnesol whereas the MTL a and MTL α haploids were on average 2- and 4-times more sensitive, respectively. In the critical range from 10-40 µM farnesol their cell death values were in the ratio of 1:2:4. Very similar results were obtained with two matched sets of MAT a , MAT α, and MAT a /α Saccharomyces cerevisiae strains. Conclusion: We propose that the observed MTL dependence of farnesol is based on differentially regulated mechanisms of entry and efflux which determine the actual cellular concentration of farnesol. The mechanisms by which pathogens such as C. albicans tolerate the otherwise lethal effects of farnesol embrace a wide range of physiological functions, including MTL type, ubiquinone type (UQ6-UQ9), energy availability, and aerobic/anaerobic status., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Boone, Parker, Gutzmann, Atkin and Nickerson.)

Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants produced farnesol and they averaged 9.2× more farnesol in the pellet than the supernatant. Nineteen mutants had significant differences with ten mutants producing more farnesol than their SN152+ wild-type control strain while nine produced less. Seven mutants exhibited greater secretion of farnesol while two exhibited less. We examined the time course for farnesol accumulation in six mutants with the greatest accumulation differences and found that those differences persisted throughout growth and they were not time dependent. Significantly, two high-accumulating mutants did not exhibit the decay in farnesol levels during stationary phase characteristic of wild-type C. albicans, suggesting that a farnesol modification/degradation mechanism is absent in these mutants. Identifying these transcriptional regulators provides new insight into farnesol's physiological functions regarding cell cycle progression, white-opaque switching, yeast-mycelial dimorphism, and response to cellular stress., Competing Interests: Conflicts of interest The authors declare no conflict of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Genetics Society of America.)

Objectives: We asked Multiracial emerging adults' about how they racially identified on the 2020 census, why they checked those boxes, their feelings about the options available to them, and how they would change the census options. After identifying the different themes, we looked at how groups differed on outcomes of Multiracial experiences, critical reflection, and self-esteem., Method: We recruited a sample of 424 Multiracial emerging adults between the ages of 18 and 29 (67.1% female, M age = 23.5). They responded to short-answer questions and survey items. Short-answer responses were coded into categories based on the themes identified, and associations with scales were examined using an analysis of variance and t test., Results: Three themes were identified for reasons for selections on the census: identity-driven, accuracy-driven, and externally driven. Five themes represented participants' feelings about the census options, which were narrowed down to two themes (okay with the census options vs. add more census options). The accuracy-driven group reported higher scores for shifting racial expressions, challenges with racial identity, and critical reflection, as well as lower scores for self-esteem. In addition, individuals who wanted more options added to the census scored higher on challenges with racial identity and critical reflection., Conclusions: Multiracial emerging adults who seek to objectively report their racial background on the census regardless of how they identify shift racial expressions and report lower self-esteem, and like those who want more options added to the census, they experience more identity challenges but are more racially aware. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The dimorphic fungus Candida albicans is a commensal and opportunistic fungal pathogen of humans. It secretes at least four small lipophilic molecules, farnesol and three aromatic fusel alcohols. Farnesol has been identified as both a quorum sensing molecule (QSM) and a virulence factor. Our gas chromatography (GC)-based assay for these molecules exhibits high throughput, prevention of analyte loss by avoiding filtration and rotary evaporation, simultaneous cell lysis and analyte extraction by ethyl acetate, and the ability to compare whole cultures with their cell pellets and supernatants. Farnesol synthesis and secretion were separable phenomena and pellet:supernatant ratios for farnesol were high, up to 12:1. The assay was validated in terms of precision, specificity, ruggedness, accuracy, solution stability, detection limits (DL), quantitation limits (QL), and dynamic range. The DL for farnesol was 0.02 ng/µl (0.09 µM). Measurement quality was assessed by the relative error of the whole culture versus the sum of pellet and supernatant fractions (WPS). C. albicans strain SC5314 grown at 30 °C in complex and defined media (YPD and mRPMI) was assayed in biological triplicate 17 times over 3 days. Farnesol and the three aromatic fusel alcohols can be measured in the same assay. The levels of all four are greatly altered by the growth medium chosen. Significantly, the three fusel alcohols are synthesized during stationary phase, not during growth. They are secreted quickly without being retained in the cell pellet and may accumulate up to mM concentrations. KEY POINTS: • Quantitative analysis of both intra- and extracellular farnesol, and aromatic fusel oils. • High throughput, whole culture assay with simultaneous lysis and extraction. • Farnesol secretion and synthesis are distinct and separate events., (© 2022. The Author(s).)

Encounters with racial discrimination occur from various sources and contexts for Latinx youth. From a historical context, Latinx have long experienced anti-immigrant sentiment and have been treated as perpetual foreigners. This study centers the voices of U.S.-born Latinx youth and explores their experiences of discrimination in 83 in-depth interviews (15-25 years, x ~ age  = 21.27, SD = 2.10; 58% Female). Through retrospective accounts, we identified four themes across narratives: assumed (illegal) immigrant, assumed unintelligent, assumed criminal, assumed inferior. Overt and subtle discrimination occurred across contexts and from multiple sources including peers, store employees, and strangers. The findings have implications for understanding Latinx youth make meaning of past experiences of discrimination and how those experiences are interpreted later in life., (© 2022 Society for Research on Adolescence.)

Racial equality requires coalitions and solidarity across racial groups, but there continues to be racially colorblind and anti-Black attitudes within the Asian American community, a diverse community consisting of individuals with ancestral origins in East, Southeast, and South Asia. However, there is limited research on the factors that contribute to the development of these attitudes among Asian Americans. Parents could potentially play an important role in perpetuating or challenging the colorblind and anti-Black messages that pervade U.S. society. Thus, the current study investigates how 309 Asian American adolescents' (M age = 16.8; SD = 1.15; 50.5% female) perceptions of parents' racial socialization messages about race and racism relate to the youth's racial attitudes. Latent profiles of youth's perceptions of mothers' and fathers' racial socialization messages and their associations with colorblind racial attitudes and anti-Black attitudes were examined. For mothers, three socialization profiles were identified: Race Avoidant, Race Hesitant, and Race Embracing; for fathers, two socialization profiles were identified: Race Avoidant and Race Embracing. Adolescents with Race Embracing mothers reported less anti-Black attitudes compared to those who had Race Hesitant mothers. For fathers, there were no differences among the profiles and anti-Black attitudes. However, surprisingly, adolescents with Race Embracing fathers were more likely to have colorblind racial attitudes compared to those with Race Avoidant fathers. The findings highlight the importance of racial socialization in the development of Asian American adolescents' racial attitudes to continue fighting for interracial solidarity., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The field of psychology is coming toward a critical juncture; scholars are increasingly recognizing that race, ethnicity, and culture play important roles in their fields of study, but do not always have the language to integrate race and culture into their own work. Furthermore, common conceptions of race may systematically exclude those from multiple racial and ethnic backgrounds in favor of fixed and discrete racial categories that ultimately perpetuate white supremacy. Meanwhile, as the Multiracial population of the U.S. is growing at an unprecedented rate, psychologists need language to acknowledge this population in their studies and pursue research to advance the field's knowledge of this diverse group and its many subpopulations. In an attempt to educate psychologists across subfields and disciplines, we provide a detailed account of preferred terms related to race and ethnicity with emphasis on ways to think about and talk about Multiracial populations in the United States. While preferred terms may change across time, the aim of this article is to provide psychologists with the tools to begin nuanced and necessary discussions about how race informs their research and the populations they work with in uniform and nonstigmatizing ways. By highlighting terminology related to those of multiple racial and ethnic backgrounds, we demystify and legitimize these rapidly growing but often hidden populations. Different perspectives on various terms are provided throughout to set psychologists on the path to beginning more race-conscious conversations and scientific inquiries into the experiences of Multiracial Americans and those from other marginalized racial-ethnic groups. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

This study investigated the main and interactive effects of identity-based challenges, discrimination, and Multiracial pride on psychological distress in Biracial emerging adults. Additionally, we examined whether these associations may differ by Biracial sub-group (e.g., Black-White, Asian-White, Latinx-White, and minority-minority) given their unique racial experiences. Participants were 326 Biracial emerging adults ( M age = 19.57 years old; 75.2% female) recruited from three public universities in the United States for an online survey. For all Biracial groups, identity-based challenges were associated with greater psychological distress. After testing a series of competing multi-group regression models, results indicated that the relations between distress and our predictors: identity-based challenges, discrimination, and Multiracial pride do indeed differ across Biracial sub-group. The most apparent and unique differences were displayed by the Black-White Biracial sub-group. These findings highlight identity-based challenges as a unique risk in the Biracial population and suggest that a principled comparison between Biracial sub-groups is necessary to tease apart group-specific associations between these constructs and psychological distress., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to report

This qualitative interview study investigated the types of parental racial-ethnic socialization messages received by Multiracial American youth over the course of their development. The Multiracial population in America is the largest demographic group among individuals under the age of 18 (Saulny, 2011), but there is a dearth of research about the development of this rapidly growing population. Multiracial youth are members of multiple racial-ethnic groups. Thus, racial-ethnic socialization is particularly complex for Multiracial families because parents typically have different racial backgrounds and experiences compared to their children. Interviews were conducted with 20 Multiracial emerging adult college students ( M age = 20.55; 10 male, 10 female) of diverse racial backgrounds to identify the types of parental racial-ethnic socialization messages they received growing up. Using thematic analysis (Braun & Clarke, 2006), nine themes of racial-ethnic socialization content emerged: Cultural socialization, racial identity socialization, preparation for bias socialization, colorblind socialization, race-conscious socialization, diversity appreciation socialization, negative socialization, exposure to diversity socialization, and silent socialization. This research advances the literature by (a) identifying domains of racial-ethnic socialization messages for Multiracial American families, (b) examining a diverse sample of male and female Multiracial youth, (c) differentiating monoracial versus Multiracial socialization messages, and (d) distinguishing the unique connotations of egalitarian socialization messages (e.g., colorblind, race-conscious, diversity appreciation). The findings have important implications for understanding the development of Multiracial American individuals and families. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Multiracial children are the largest demographic group in the United States among individuals under the age of 18 (Pew Research Center, 2015), but their developmental processes are understudied. Parents and caregivers play an important role in preparing youth to navigate racialized society by teaching them to understand what it means to be a member of a racial-ethnic group (Hughes et al., 2006). However, this process is more complex in multiracial families, where youth belong to multiple racial-ethnic groups. Thus, the purpose of the present study was to develop and validate the first measure of racial-ethnic socialization for Multiracial youth, the Multiracial Youth Socialization (MY-Soc) Scale, to assess the unique messages that are communicated in multiracial families regarding topics of race, ethnicity, and culture. Using a sample of 901 Multiracial emerging adults ( m age = 22.43), we separately captured the socialization practices of two of the youths' primary caregivers from the youths' perspective. Exploratory and confirmatory factor analyses supported a 62-item scale measuring eight types of socialization: Navigating Multiple Heritages Socialization, Multiracial Identity Socialization, Preparation for Monoracism Socialization, Negative Socialization, Colorblind Socialization, Diversity Appreciation Socialization, Race-Conscious Socialization, and Silent Socialization. The MY-Soc Scale was also supported by validity and reliability tests. This study contributes an important tool for scholars and practitioners to learn which racial-ethnic socialization messages are promotive for Multiracial youth development in different contexts. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

This paper developed and validated a new measure of support for the Black Lives Matter (BLM) movement among a racially-ethnically diverse sample of college students. The measure focuses on the movement's principles of Black liberation, intersectionality, and alliance building. Participants included 1934 college students (75% female) from a large public Southwestern university. The factor structure was supported by exploratory and confirmatory factor analyses, resulting in an 18-item measure, Support for Black Lives Matter, with two underlying factors. Black Liberation includes 12 items representing support for BLM because of awareness of and challenging structural inequality and racism experienced by Black individuals. Intersectional Values includes six items representing support for BLM because it embraces and affirms marginalized populations within the Black community, especially disabled Blacks, queer Blacks, Black women, and Black families with children. Evidence of criterion-related validity was demonstrated with racial group differences in support of BLM factors. Evidence of convergent validity was supported by significant positive correlations between support for BLM factors and critical consciousness (including awareness of racism, classism, and heterosexism), and negative correlations between support for BLM factors and subtle racist attitudes toward Blacks. Measurement invariance was evident between White, Black, Asian American, Latinx, and Multiracial participants. Implications and suggestions for use of the new measure are discussed., (© 2021 Society for Community Research and Action.)

As Asian Americans continue to be one of the fastest growing populations in a rapidly diversifying United States (Lee, 2015), understanding how Asian American parents socialize their children about race and racism and how this contributes to development remains an important question (Chang, 2016; García Coll et al., 1996). Using a sample of 228 Asian American emerging adults (70% female, M age = 20.23), we examined profiles of parental racial-ethnic socialization messages and their relationships with racial-ethnic identity and social connectedness outcomes. Results suggested 3 profiles. The guarded separation socialization group reported receiving the most frequent messages about maintaining their heritage culture and avoiding outgroups. The passive and active integration socialization groups also received frequent messages about maintaining heritage culture, but very few messages about avoiding outgroups or minimizing the significance of race. The active integration socialization group received the most messages about becoming American, treating everyone equally, and respecting diverse cultures, compared to the passive integration socialization group, which reported receiving few of these messages. Participants in the active integration profile reported significantly higher levels of cognitive clarity and affective pride regarding their racial-ethnic identity compared to the other two profiles, while individuals in the passive and active integration profiles reported significantly higher levels of social connectedness than those in guarded separation profile. These findings highlight the importance of using a holistic lens to understand Asian American youths' perceptions of how their parents engage in racial-ethnic socialization across multiple domains. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objectives: The literature on Asian Americans yields mixed findings regarding the protective effects of ethnic identity on the racial discrimination-psychological distress link (Park, Schwartz, Lee, Kim, & Rodriguez, 2013). This study introduces metastereotype awareness (MSA; the awareness one has regarding stereotypes others hold of their group) into this relationship, focusing on the stereotype of Asians as unsociable., Method: We examined a 3-way interaction between racial discrimination, ethnic identity commitment, and MSA on a latent psychological distress variable among a sample of Asian American emerging adults attending predominantly White universities (N = 276, 60% female, mean age = 20)., Results: Structural equation modeling suggested a significant 3-way interaction in which the protective role of ethnic identity commitment varied depending on the level of MSA. Specifically, high levels of ethnic identity commitment buffered the racial discrimination-psychological distress link for individuals reporting high levels of MSA. Furthermore, low levels of ethnic identity commitment buffered the discrimination-psychological distress link for Asian American students reporting low levels of MSA. In contrast, a positive link between discrimination and psychological distress persisted for Asian American students reporting a combination of high ethnic identity and low MSA and vice versa., Conclusion: In summary, Asian American college students who had high levels of both ethnic identity commitment and MSA or low levels on both variables were protected from psychological distress associated with racial discrimination. These findings illuminate the nuanced relationship between racial discrimination, ethnic identity commitment, and MSA in predicting psychological distress outcomes for Asian Americans. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

In this brief report, the authors investigate how different types of parental racial-ethnic socialization messages (i.e., cultural socialization/pluralism, promotion of mistrust, and preparation for racial bias) moderate the relationship between racial discrimination and psychological distress in a sample of 187 Asian American adolescents. Results indicated a significant positive relationship between racial discrimination and psychological distress. Cultural socialization/pluralism and promotion of mistrust also moderated the racial discrimination and psychological distress link. Specifically, for adolescents reporting low frequencies of cultural socialization/pluralism messages, discrimination was positively associated with psychological distress, suggesting cultural socialization/pluralism messages may be a protective factor. Discrimination was also positively associated with psychological distress for adolescents reporting high frequencies of promotion of mistrust, suggesting that promotion of mistrust may be a risk factor. Overall, the findings emphasize the important role that racial-ethnic socialization messages can have on psychological distress among Asian American adolescents who experience racial discrimination. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Although culture influences all human beings, there is an assumption in American psychology that culture matters more for members of certain groups. This article identifies and provides evidence of the cultural (mis)attribution bias: a tendency to overemphasize the role of culture in the behavior of racial/ethnic minorities, and to underemphasize it in the behavior of Whites. Two studies investigated the presence of this bias with an examination of a decade of peer reviewed research conducted in the United States (N = 434 articles), and an experiment and a survey with psychology professors in the United States (N = 361 psychologists). Archival analyses revealed differences in the composition of samples used in studies examining cultural or noncultural psychological phenomena. We also find evidence to suggest that psychologists in the United States favor cultural explanations over psychological explanations when considering the behavior and cognition of racial/ethnic minorities, whereas the opposite pattern emerged in reference to Whites. The scientific ramifications of this phenomenon, as well as alternatives to overcome it, are discussed in detail. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)

Candida albicans excretes E,E-farnesol as a virulence factor and quorum sensing molecule that prevents the yeast to hyphal conversion. Polke et al. (2016) identified eed1Δ/Δ as the first farnesol hypersensitive mutant of C. albicans. eed1Δ/Δ also excretes 10X more farnesol and while able to form hyphae, it cannot maintain hyphae. This mutant enables new research into unanswered questions, including the existence of potential farnesol receptors and transporters, regulation of farnesol synthesis, and relationships among farnesol, germ tube formation and hyphal maintenance. The eed1 farnesol hypersensitivity can be explained by higher internal concentrations of farnesol or lower thresholds for response. One possibility invokes misexpression of a transporter. Saccharomyces cerevisiae and C. albicans have transporters for farnesylated peptides, like the a-factor pheromone, which could potentially also transport farnesol for virulence and quorum sensing. Significantly, these transporters are repressed in MTLa/MTLα C. albicans. An evolutionary pressure for C. albicans to become diploid could derive from its use of farnesol. Alternatively, maintenance of hyphal growth may increase the farnesol response threshold. Finally, Dpp1p, Dpp2p and Dpp3p are non-specific pyrophosphatases responsible for farnesol synthesis. Changes in expression of these enzymes do not explain differences in farnesol levels implicating involvement of additional factors like a scaffolding molecule., (© 2016 John Wiley & Sons Ltd.)

The polymorphic commensal fungus Candida albicans causes life-threatening disease via bloodstream and intra-abdominal infections in immunocompromised and transplant patients. Although host immune evasion is a common strategy used by successful human fungal pathogens, C. albicans provokes recognition by host immune cells less capable of destroying it. To accomplish this, C. albicans white cells secrete a low-molecular-weight chemoattractive stimulant(s) of macrophages, a phagocyte that they are able to survive within and eventually escape from. C. albicans opaque cells do not secrete this chemoattractive stimulant(s). We report here a physiological mechanism that contributes to the differences in the interaction of C. albicans white and opaque cells with macrophages. E,E-Farnesol, which is secreted by white cells only, is a potent stimulator of macrophage chemokinesis, whose activity is enhanced by yeast cell wall components and aromatic alcohols. E,E-farnesol results in up to an 8.5-fold increase in macrophage migration in vitro and promotes a 3-fold increase in the peritoneal infiltration of macrophages in vivo. Therefore, modulation of farnesol secretion to stimulate host immune recognition by macrophages may help explain why this commensal is such a successful pathogen., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

The nonsense-mediated mRNA decay (NMD) pathway is a specialized pathway that triggers the rapid degradation of select mRNAs. Initially, identified as a pathway that degrades mRNAs with premature termination codons, NMD is now recognized as a pathway that also regulates some natural mRNAs. Since natural mRNAs do not typically contain premature termination codons, these mRNAs contain features that target them to NMD. In Saccharomyces cerevisiae mRNAs with atypically long 3'-UTRs are usually degraded by NMD, however in some conditions a constitutively expressed SSY5 mRNA with multiple NMD targeting signals including an atypically long 3'-UTR is an exception. We investigated the features of the SSY5 mRNAs that confer immunity to NMD. We found that the SSY5 mRNA 3'-UTRs are sufficient to target NMD insensitive mRNA to the pathway. Replacing the SSY5 3'-UTRs with the cyc1-512 3'-UTRs, known to target mRNAs to NMD or with the CYC1 3'-UTR, known not to target mRNAs to NMD, resulted in production of SSY5 mRNAs that were regulated by NMD. These observations suggest that the SSY5 mRNAs require sequences both within the 5'-UTR and/or ORF as well as the 3'-UTR to escape decay by NMD.

Quorum sensing by farnesol in Candida albicans inhibits filamentation and may be directly related to its ability to cause both mucosal and systemic diseases. The Ras1-cyclic AMP signaling pathway is a target for farnesol inhibition. However, a clear understanding of the downstream effectors of the morphological farnesol response has yet to be unraveled. To address this issue, we screened a library for mutants that fail to respond to farnesol. Six mutants were identified, and the czf1Δ/czf1Δ mutant was selected for further characterization. Czf1 is a transcription factor that regulates filamentation in embedded agar and also white-to-opaque switching. We found that Czf1 is required for filament inhibition by farnesol under at least three distinct environmental conditions: on agar surfaces, in liquid medium, and when embedded in a semisolid agar matrix. Since Efg1 is a transcription factor of the Ras1-cyclic AMP signaling pathway that interacts with and regulates Czf1, an efg1Δ/efg1Δ czf1Δ/czf1Δ mutant was tested for filament inhibition by farnesol. It exhibited an opaque-cell-like temperature-dependent morphology, and it was killed by low farnesol levels that are sublethal to wild-type cells and both efg1Δ/efg1Δ and czf1Δ/czf1Δ single mutants. These results highlight a new role for Czf1 as a downstream effector of the morphological response to farnesol, and along with Efg1, Czf1 is involved in the control of farnesol-mediated cell death in C. albicans.

The objective of the research was to determine the optimum application rates of soybean peroxidase (SBP) plus peroxide (SBPP) for reducing odorous VOC emissions from swine manure. Industrial-grade SBP was applied in combination with liquid hydrogen peroxide (H(2)O(2)) or powdered calcium peroxide (CaO(2)) to standard phenolic solutions and swine manure, and emissions were measured in a wind tunnel. The primary odorant in the untreated manure was 4-methylphenol, which accounted for 68-81% of the odor activity value. At the optimum application rate of SBPP (50 g L(-1)), 4-methylphenol emissions were reduced from the swine manure by 62% (H(2)O(2)) and 98% (CaO(2)) after 24h (P<0.0001). The CaO(2) had a longer residence time, remaining effective for 48 h with 92% reduction in emission rates (P<0.0001), while H(2)O(2) was similar to the control at 48 h (P=0.28)., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Nonsense-mediated mRNA decay is a highly conserved pathway that degrades mRNAs with premature termination codons. These mRNAs include mRNAs transcribed from nonsense or frameshift alleles as well as wild-type mRNA with signals that direct ribosomes to terminate prematurely. This unit describes techniques to monitor steady-state mRNA levels, decay rates, and structural features of mRNAs targeted by this pathway, as well as in vivo analysis of nonsense suppression and allosuppression in the yeast Saccharomyces cerevisiae. Protocols for the structural features of mRNA include analysis of cap status, 5' and 3' untranslated region (UTR) lengths, and poly(A) tail length.

The eukaryotic nonsense-mediated mRNA (NMD) is a specialized pathway that leads to the recognition and rapid degradation of mRNAs with premature termination codons, and importantly some natural mRNAs as well. Natural mRNAs with atypically long 3'-untranslated regions (UTRs) are degraded by NMD in Saccharomyces cerevisiae. A number of S. cerevisiae mRNAs undergo alternative 3'-end processing producing mRNA isoforms that differ in their 3'-UTR lengths. Some of these alternatively 3'-end processed mRNA isoforms have atypically long 3'-UTRs and would be likely targets for NMD-mediated degradation. Here, we investigated the role NMD plays in the regulation of expression of CTR2, which encodes a vacuolar membrane copper transporter. CTR2 pre-mRNA undergoes alternative 3'-end processing to produce two mRNA isoforms with 300-nt and 2-kb 3'-UTRs. We show that both CTR2 mRNA isoforms are differentially regulated by NMD. The regulation of CTR2 mRNA by NMD has physiological consequences, since nmd mutants are more tolerant to toxic levels of copper relative to wild-type yeast cells and the copper tolerance of nmd mutants is dependent on the presence of CTR2.

A scalable four-step synthesis of the ornithine transcarbamylase inhibitor N(5)-phosphonoacetyl-l-ornithine (PALO) is achieved through boroxazolidinone protection of ornithine. Investigations in the model organism Saccharomyces cerevisiae found that, in contrast to a previous report, PALO did not influence growth rate or expression of genes involved in arginine metabolism., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Saccharomyces cerevisiae, commonly known as baker's or budding yeast, is an attractive organism for design-based engineering because it is an industrially important organism with a well-annotated genome sequence and an extensive collection of resources for molecular analyses. This chapter describes the utility of Saccharomyces Genome Database for analysis of S. cerevisiae genes and identification of homologs, strategies for integration and analysis of gene expression data, and the genetic resources available for doing experiments using S. cerevisiae.

Farnesol interacts with Candida albicans as both a quorum-sensing molecule and toxic agent, but confusion abounds regarding which conditions promote these distinct responses. Farnesol sensitivity was measured when inoculum cell history and size, temperature, and growth media were altered. Parameters for farnesol tolerance/sensitivity were defined, validating previous studies and identifying new variables, such as energy availability. This study clearly defines what farnesol concentrations are lethal to C. albicans, based on environmental conditions.

Farnesol is a quorum-sensing molecule produced by Candida albicans that has many effects, including filament inhibition of this polymorphic fungus. In the past 9 years, the effect of farnesol on C. albicans has been reported in nearly 160 publications, with early work examining its influence on morphology. This article presents an update on the literature published since 2006, focusing on points that still need to be resolved as well as identifying possible artifacts that might interfere with this goal. In addition, the regulation of C. albicans farnesol production, C. albicans' resistance/sensitivity to farnesol and the influence of farnesol on other species as well as the host are discussed. It is intriguing that we still do not know precisely how farnesol works, but interference with the Ras1-cAMP pathway is part of the story.

The nonsense-mediated mRNA decay (NMD) pathway, present in most eukaryotic cells, is a specialized pathway that leads to the recognition and rapid degradation of mRNAs with premature termination codons and, importantly, some wild-type mRNAs. Earlier studies demonstrated that aberrant mRNAs with artificially extended 3'-untranslated regions (3'-UTRs) are degraded by NMD. However, the extent to which wild-type mRNAs with long 3'-UTRs are degraded by NMD is not known. We used a global approach to identify wild-type mRNAs in Saccharomyces cerevisiae that have longer than expected 3'-UTRs, and of these mRNAs tested, 91% were degraded by NMD. We demonstrate for the first time that replacement of the natural, long 3'-UTR from wild-type PGA1 mRNA, which encodes a protein that is important for cell wall biosynthesis, with a short 3'-UTR renders it immune to NMD. The natural PGA1 3'-UTR is sufficient to target a NMD insensitive mRNA for decay by the NMD pathway. Finally, we show that nmd mutants are sensitive to Calcofluor White, which suggests that the regulation of PGA1 and other cell wall biosynthesis proteins by NMD is physiologically significant.

The opportunistic fungal pathogen Candida albicans is a part of the normal flora but it also causes systemic candidiasis if it reaches the bloodstream. Upon being phagocytized by macrophages, an important component of innate immunity, C. albicans rapidly upregulates a set of arginine biosynthetic genes. Arginine, urea, and CO2 induced hyphae in a density-dependent manner in wild-type, cph1/cph1, and rim101/rim101 strains but not in efg1/efg1 or cph1/cph1 efg1/efg1 strains. Arginase (Car1p) converts arginine to urea, which in turn is degraded by urea amidolyase (Dur1,2p) to produce CO2, a signal for hyphal switching. We used a dur1,2/dur1,2 mutant (KWN6) and the complemented strain, KWN8 (dur1,2/dur1,2::DUR1,2/DUR1,2) to study germ tube formation. KWN6 could not make germ tubes in the presence of arginine or urea but did in the presence of 5% CO(2), which bypasses Dur1,2p. We also tested the effect of arginine on the interaction between the macrophage line RAW 264.7 and several strains of C. albicans. Arginine activated an Efg1p-dependent yeast-to-hypha switch, enabling wild-type C. albicans and KWN8 to escape from macrophages within 6 h, whereas KWN6 was defective in this regard. Additionally, two mutants that cannot synthesize arginine, BWP17 and SN152, were defective in making hyphae inside the macrophages, whereas the corresponding arginine prototrophs, DAY286 and SN87, formed germ tubes and escaped from macrophages. Therefore, metabolism of arginine by C. albicans controls hyphal switching and provides an important mechanism for escaping host defense.

Colonization by the fungal pathogen Candida albicans varies significantly, depending upon the pH and availability of oxygen. Because of our interest in extracellular molecules as potential quorum-sensing molecules, we examined the physiological conditions which regulate the production of the aromatic alcohols, i.e., phenethyl alcohol, tyrosol, and tryptophol. The production of these fusel oils has been well studied for Saccharomyces cerevisiae. Our data show that aromatic alcohol yields for C. albicans are determined by growth conditions. These conditions include the availability of aromatic amino acids, the pH, oxygen levels, and the presence of ammonium salts. For example, for wild-type C. albicans, tyrosol production varied 16-fold merely with the inclusion of tyrosine or ammonium salts in the growth medium. Aromatic alcohol production also depends on the transcription regulator Aro80p. Our results are consistent with aromatic alcohol production-aromatic transaminases (gene products for ARO8 and ARO9), aromatic decarboxylase (ARO10), and alcohol dehydrogenase (ADH)-via the fusel oil pathway. The expression of ARO8, ARO9, and ARO10 is also pH dependent. ARO8 and ARO9 were alkaline upregulated, while ARO10 was alkaline downregulated. The alkaline-dependent change in expression of ARO8 was Rim101 independent, while the expression of ARO9 was Rim101 dependent.

Candida albicans is a dimorphic fungus that can interconvert between yeast and filamentous forms. Its ability to regulate morphogenesis is strongly correlated with virulence. Tup1, a transcriptional repressor, and the signaling molecule farnesol are both capable of negatively regulating the yeast to filamentous conversion. Based on this overlap in function, we tested the hypothesis that the cellular response to farnesol involves, in part, the activation of Tup1. Tup1 functions with the DNA binding proteins Nrg1 and Rfg1 as a transcription regulator to repress the expression of hypha-specific genes. The tup1/tup1 and nrg1/nrg1 mutants, but not the rfg1/rfg1 mutant, failed to respond to farnesol. Treatment of C. albicans cells with farnesol caused a small but consistent increase in both TUP1 mRNA and protein levels. Importantly, this increase corresponds with the commitment point, beyond which added farnesol no longer blocks germ tube formation, and it correlates with a strong decrease in the expression of two Tup1-regulated hypha-specific genes, HWP1 and RBT1. Tup1 probably plays a direct role in the response to farnesol because farnesol suppresses the haploinsufficient phenotype of a TUP1/tup1 heterozygote. Farnesol did not affect EFG1 (a transcription regulator of filament development), NRG1, or RFG1 mRNA levels, demonstrating specific gene regulation in response to farnesol. Furthermore, the tup1/tup1 and nrg1/nrg1 mutants produced 17- and 19-fold more farnesol, respectively, than the parental strain. These levels of excess farnesol are sufficient to block filamentation in a wild-type strain. Our data are consistent with the role of Tup1 as a crucial component of the response to farnesol in C. albicans.

Candida albicans cells of opposite mating types are thought to conjugate during infection in mammalian hosts, but paradoxically, the mating-competent opaque state is not stable at mammalian body temperatures. We found that anaerobic conditions stabilize the opaque state at 37 degrees C, block production of farnesol, and permit in vitro mating at 37 degrees C at efficiencies of up to 84%. Aerobically, farnesol prevents mating because it kills the opaque cells necessary for mating, and as a corollary, farnesol production is turned off in opaque cells. These in vitro observations suggest that naturally anaerobic sites, such as the efficiently colonized gastrointestinal (GI) tract, could serve as niches for C. albicans mating. In a direct test of mating in the mouse GI tract, prototrophic cells were obtained from auxotrophic parent cells, confirming that mating will occur in this organ. These cells were true mating products because they were tetraploid, mononuclear, and prototrophic, and they contained the heterologous hisG marker from one of the parental strains.

A method for determining mRNA half-lives in the polymorphic fungus Candida albicans is described. It employs growth in a defined medium, the inhibition of transcription with thiolutin (10-20 microg/mL), and quantitative Northern blotting. The method is effective for the A72, SC5314, and CAI-4 strains of C. albicans, and for mRNAs that have a wide variety of decay rates and steady-state abundances. The range of half-lives detected (from 4-168 min) shows that this method is effective for mRNAs with widely varying half-lives. The mRNA decay rates obtained are compared with those for orthologous mRNAs from Saccharomyces cerevisiae. This procedure should work for a broad range of C. albicans strains and can be adapted to other fungal species.

Candida albicans is a diploid fungus that undergoes a morphological transition between budding yeast, hyphal, and pseudohyphal forms. The morphological transition is strongly correlated with virulence and is regulated in part by quorum sensing. Candida albicans produces and secretes farnesol that regulates the yeast to mycelia morphological transition. Mutants that fail to synthesize or respond to farnesol could be locked in the filamentous mode. To test this hypothesis, a collection of C. albicans mutants were isolated that have altered colony morphologies indicative of the presence of hyphal cells under environmental conditions where C. albicans normally grows only as yeasts. All mutants were characterized for their ability to respond to farnesol. Of these, 95.9% fully or partially reverted to wild-type morphology on yeast malt (YM) agar plates supplemented with farnesol. All mutants that respond to farnesol regained their hyphal morphology when restreaked on YM plates without farnesol. The observation that farnesol remedial mutants are so common (95.9%) relative to mutants that fail to respond to farnesol (4.1%) suggests that farnesol activates and (or) induces a pathway that can override many of the morphogenesis defects in these mutants. Additionally, 9 mutants chosen at random were screened for farnesol production. Two mutants failed to produce detectable levels of farnesol.

The nonsense-mediated mRNA decay (NMD) pathway has historically been thought of as an RNA surveillance system that degrades mRNAs with premature translation termination codons, but the NMD pathway of Saccharomyces cerevisiae has a second role regulating the decay of some wild-type mRNAs. In S. cerevisiae, a significant number of wild-type mRNAs are affected when NMD is inactivated. These mRNAs are either wild-type NMD substrates or mRNAs whose abundance increases as an indirect consequence of NMD. A current challenge is to sort the mRNAs that accumulate when NMD is inactivated into direct and indirect targets. We have developed a bioinformatics-based approach to address this challenge. Our approach involves using existing genomic and function databases to identify transcription factors whose mRNAs are elevated in NMD-deficient cells and the genes that they regulate. Using this strategy, we have investigated a coregulated set of genes. We have shown that NMD regulates accumulation of ADR1 and GAL4 mRNAs, which encode transcription activators, and that Adr1 is probably a transcription activator of ATS1. This regulation is physiologically significant because overexpression of ADR1 causes a respiratory defect that mimics the defect seen in strains with an inactive NMD pathway. This strategy is significant because it allows us to classify the genes regulated by NMD into functionally related sets, an important step toward understanding the role NMD plays in the normal functioning of yeast cells.

Concentrations of (E,E)-farnesol needed to inhibit germ tube formation were determined for Candida albicans strains A72 and SC5314 by using six different conditions known to trigger germination. For defined media, 1 to 2 microM farnesol was sufficient. However, with serum at 2 to 20%, up to 250 microM farnesol was required. Farnesol blocked germ tube formation but did not block elongation of existing germ tubes.

Saccharomyces cerevisiae Upf1p is a 971-amino-acid protein that is required for the nonsense-mediated mRNA decay (NMD) pathway, a pathway that degrades mRNAs with premature translational termination codons. We have identified a two-hybrid interaction between Upf1p and the nuclear pore (Nup) proteins, Nup100p and Nup116p. Both nucleoporins predominantly localize to the cytoplasmic side of the nuclear pore and participate in mRNA transport. The two-hybrid interaction between Upf1p and the nuclear pore proteins, Nup100p and Nup116p, is dependent on the presence of the C-terminal 158 amino acids of Upf1p. Nup100p and Nup116p can be co-immunoprecipitated from whole-cell extracts with Upf1p, confirming in vitro the interaction identified by the two-hybrid analysis. Finally, we see a genetic interaction between UPF1 and NUP100. The growth of upf1Delta, can1-100 cells is inhibited by canavanine. The deletion of NUP100 allows upf1Delta, can1-100 cells to grow in the presence of canavanine. Physiologically, the interaction between Upf1p and the nuclear pore proteins, Nup100p and Nup116p, is significant because it suggests a mechanism to ensure that Upf1p associates with newly synthesized mRNA as it is transported from the nucleus to the cytoplasm prior to the pioneer round of translation.

Saccharomyces cerevisiae ATS1 (alpha-tubulin suppressor 1) was originally identified as a high-copy suppressor of class two alpha-tubulin mutations and was proposed to have a regulatory role in coordinating the microtubule state with the cell cycle. Here, we show that Ats1p interacts with Nap1p, a cytoplasmic protein that regulates the activity of the Cdc28p/Clb2p complex. Loss of Nap1p results in a delayed switch from polar to isotropic bud growth. The delayed switch results in elongated buds. Nap1p and Ats1p interact in two-hybrid and co-immunoprecipitation assays. Both nap1Delta and ats1Delta cells have a Clb2p-dependent elongated bud morphology. Deletion of ATS1 partially suppresses the elongated bud morphology and benomyl resistance of nap1Delta mutants. Our results suggest Ats1p might regulate coordination of the microtubule state with the cell cycle through an interaction with Nap1p.

mRNAs containing premature translation termination codons (nonsense mRNAs) are targeted for deadenylation-independent degradation in a mechanism that depends on Upf1p, Upf2p and Upf3p. This decay pathway is often called nonsense- mediated mRNA decay (NMD). Nonsense mRNAs are decapped by Dcp1p and then degraded 5' to 3' by Xrn1p. In the yeast Saccharomyces cerevisiae, a significant number of wild-type mRNAs accumulate in upf mutants. Wild-type PPR1 mRNA is one of these mRNAs. Here we show that PPR1 mRNA degradation depends on the Upf proteins, Dcp1p, Xrn1p and Hrp1p. We have mapped an Upf1p-dependent destabilizing element to a region located within the 5'-UTR and the first 92 bases of the PPR1 ORF. This element targets PPR1 mRNA for Upf-dependent decay by a novel mechanism.