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This article, published in the New Phytologist journal, discusses the behavior and internalization of the AtRGS1 protein in response to different pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) in Arabidopsis thaliana. The study found that AtRGS1 exhibits distinct behaviors and endocytic pathways depending on the type of PAMP/DAMP, and that its phosphorylation pattern contributes to its organization and endocytic model. The research provides insights into the mechanisms of plant immune responses. [Extracted from the article]

Objective Despite heterogeneity among Pacific Islanders, most studies aggregate them regardless of origin. Thus, limited information is available about perinatal outcomes among various subgroups of Pacific Islanders in the United States, including immigrants from the Republic of the Marshall Islands. We sought to evaluate perinatal outcomes among Marshallese women. Methods We conducted a cross-sectional study of women with at least one singleton live birth between 1997 and 2013 in two Arkansas counties using birth certificate data from the Arkansas Department of Health. Unadjusted and adjusted prevalence ratios (PR) and 95% confidence intervals (CI) were calculated from modified Poisson regression models. Results Of the 91,662 singleton births in both counties during the study period, 2488 were to Marshallese women. In adjusted analyses, Marshallese women had higher prevalence of 'other medical risk factors' (PR = 1.47; 95% CI 1.30, 1.65) than NH White women. Marshallese women had higher rates of precipitous labor and fetal distress during labor compared to NH White women (PR = 2.65; 95% CI 2.22, 3.17 and 1.89; 95% CI 1.62, 2.21, respectively). Marshallese were also more likely to have tocolysis (PR = 1.43; 95% CI 1.16, 1.76), forceps (PR = 1.68; 95% CI 1.16, 2.43) or vacuum (PR = 1.89; 95% CI 1.60, 2.22) used in delivery and cesarean section (PR = 1.13; 95% CI 1.01, 1.27). Marshallese infants had higher rates of anemia (PR = 3.10; 95% CI 2.01, 4.77), birth injury (PR = 2.13; 95% CI 1.50, 3.03), assisted ventilation < 30 min (PR = 2.11; 95% CI 1.64, 2.71), preterm birth (PR = 1.67; 95% CI 1.50, 1.83), and small-for-gestational age (PR = 1.25; 95% CI 1.12, 1.39) than NH White infants. Conclusions Marshallese women and infants had higher rates of adverse perinatal outcomes compared to their NH White counterparts. Additional studies are needed to determine if perinatal outcomes among the Marshallese differed from other Pacific Islander subgroups., Author(s): Wendy N. Nembhard [sup.1] [sup.2] , Britni L. Ayers [sup.3] , R. Thomas Collins [sup.6] , Xiaoyi Shan [sup.2] [sup.4] , Nader Z. Rabie [sup.7] , Di Chang [sup.5] [...]

Background: The plasma membrane (PM) proteins function in a highly dynamic state, including protein trafficking and protein homeostasis, to regulate various biological processes. The dwell time and colocalization of PM proteins are considered to be two important dynamic features determining endocytosis and protein interactions, respectively. Dwell-time and colocalization detected using traditional fluorescence microscope techniques are often misestimated due to bulk measurement. In particular, analyzing these two features of PM proteins at the single-molecule level with spatiotemporal continuity in plant cells remains greatly challenging. Results: We developed a single molecular (SM) kymograph method, which is based on variable angle-total internal reflection fluorescence microscopy (VA-TIRFM) observation and single-particle (co-)tracking (SPT) analysis, to accurately analyze the dwell time and colocalization of PM proteins in a spatial and temporal manner. Furthermore, we selected two PM proteins with distinct dynamic behaviors, including AtRGS1 (Arabidopsis regulator of G protein signaling 1) and AtREM1.3 (Arabidopsis remorin 1.3), to analyze their dwell time and colocalization upon jasmonate (JA) treatment by SM kymography. First, we established new 3D (2D+t) images to view all trajectories of the interest protein by rotating these images, and then we chose the appropriate point without changing the trajectory for further analysis. Upon JA treatment, the path lines of AtRGS1-YFP appeared curved and short, while the horizontal lines of mCherry-AtREM1.3 demonstrated limited changes, indicating that JA might initiate the endocytosis of AtRGS1. Analysis of transgenic seedlings coexpressing AtRGS1-YFP/mCherry-AtREM1.3 revealed that JA induces a change in the trajectory of AtRGS1-YFP, which then merges into the kymography line of mCherry-AtREM1.3, implying that JA increases the colocalization degree between AtRGS1 and AtREM1.3 on the PM. These results illustrate that different types of PM proteins exhibit specific dynamic features in line with their corresponding functions. Conclusions: The SM-kymograph method provides new insight into quantitively analyzing the dwell time and correlation degree of PM proteins at the single-molecule level in living plant cells. [ABSTRACT FROM AUTHOR]

The lack of United States population‐based data on Turner syndrome limits assessments of prevalence and associated characteristics for this sex chromosome abnormality. Therefore, we collated 2000–2017 data from seven birth defects surveillance programs within the National Birth Defects Prevention Network. We estimated the prevalence of karyotype‐confirmed Turner syndrome diagnosed within the first year of life. We also calculated the proportion of cases with commonly ascertained birth defects, assessed associations with maternal and infant characteristics using prevalence ratios (PR) with 95% confidence intervals (CI), and estimated survival probability. The prevalence of Turner syndrome of any pregnancy outcome was 3.2 per 10,000 female live births (95% CI = 3.0–3.3, program range: 1.0–10.4), and 1.9 for live birth and stillbirth (≥20 weeks gestation) cases (95% CI = 1.8–2.1, program range: 0.2–3.9). Prevalence was lowest among cases born to non‐Hispanic Black women compared to non‐Hispanic White women (PR = 0.5, 95% CI = 0.4–0.6). Coarctation of the aorta was the most common defect (11.6% of cases), and across the cohort, individuals without hypoplastic left heart had a five‐year survival probability of 94.6%. The findings from this population‐based study may inform surveillance practices, prenatal counseling, and diagnosis. We also identified racial and ethnic disparities in prevalence, an observation that warrants further investigation. [ABSTRACT FROM AUTHOR]

Plants and microbial pathogens often engage in a fierce war that determines their survival. Host plants have evolved sophisticated regulatory mechanisms to fine-tune defense responses to counter attacks from pathogens, while pathogens often hijack the lipid-derived phytohormone jasmonate to cause hormonal signaling imbalances for efficient infection. This review focuses on the jasmonate-based warfare between host plants and pathogenic intruders, and further discusses approaches to uncouple plant growth and defense tradeoffs in crop breeding. [ABSTRACT FROM AUTHOR]

Background: Critical congenital heart defects (CCHDs) are one of the most common types of birth defects and can lead to significant morbidity and mortality along with surgical or catheter interventions within the first year of life. This report updates previously published estimates of CCHD prevalence with the latest population‐based surveillance data from 19 birth defect surveillance programs. Methods: The U.S. population‐based surveillance programs submitted data on identified cases of 12 CCHDs and co‐occurring cardiovascular and chromosomal birth defects from 2014 to 2018. We estimated prevalence by program type and maternal and infant characteristics. Among nine programs with active case ascertainment that collect more than live births, we estimated the percentage of co‐occurring cardiovascular and chromosomal birth defects for the 12 CCHDs. Results: We identified 18,587 cases of CCHD among all participating programs. Overall CCHD prevalence was 19.6 per 10,000 live births among all 19 programs and 20.2 per 10,000 live births among active programs. Among maternal racial/ethnic groups, infants/fetuses born to American Indian/Alaska Native mothers showed the highest overall prevalence for all CCHDs (28.3 per 10,000) along with eight of the 12 individual CCHDs. Among 7,726 infants/fetuses with CCHD from active case ascertainment programs, 15.8% had at least one co‐occurring chromosomal birth defect. Conclusion: Our study provides prevalence estimates for CCHDs by maternal and infant characteristics along with co‐occurrence with cardiovascular and chromosomal birth defects among infants/fetuses with CCHD using one of the largest and most recent cohorts since the implementation of widespread CCHD screening. These data can provide a basis for future research to better understand risk factors for these defects. [ABSTRACT FROM AUTHOR]

The bias is in the system: In Arabidopsis, the nutrient glucose and the bacterial peptide flg22 both induce the internalization of the RGS protein AtRGS1 but trigger different transcriptional responses. Watkins et al. found that the distinct changes in cellular responses were mediated by segregated signaling pathways. Glucose and flg22 induced the internalization of AtRGS1 through different forms of endocytosis and required different phosphorylation events, endocytic adaptor proteins, and G protein subunits. Because of these systemic biases, only flg22 triggered MAPK and Ca2+ signaling before changes in gene expression. Thus, AtRGS1 links the appropriate signaling outputs to the corresponding signaling inputs through differences in the architecture of the signaling pathways that originate at the plasma membrane. In animals, endocytosis of a seven-transmembrane GPCR is mediated by arrestins to propagate or arrest cytoplasmic G protein–mediated signaling, depending on the bias of the receptor or ligand, which determines how much one transduction pathway is used compared to another. In Arabidopsis thaliana, GPCRs are not required for G protein–coupled signaling because the heterotrimeric G protein complex spontaneously exchanges nucleotide. Instead, the seven-transmembrane protein AtRGS1 modulates G protein signaling through ligand-dependent endocytosis, which initiates derepression of signaling without the involvement of canonical arrestins. Here, we found that endocytosis of AtRGS1 initiated from two separate pools of plasma membrane: sterol-dependent domains and a clathrin-accessible neighborhood, each with a select set of discriminators, activators, and candidate arrestin-like adaptors. Ligand identity (either the pathogen-associated molecular pattern flg22 or the sugar glucose) determined the origin of AtRGS1 endocytosis. Different trafficking origins and trajectories led to different cellular outcomes. Thus, in this system, compartmentation with its associated signalosome architecture drives biased signaling. [ABSTRACT FROM AUTHOR]

Growth and immunity are opposing processes that compete for cellular resources, and proper resource allocation is crucial for plant survival. BSK1 plays a key role in the regulation of both growth and immunity by associating with BRI1 and FLS2, respectively. However, it remains unclear how two antagonistic signals co-opt BSK1 to induce signal-specific activation. Here we show that the dynamic spatial reorganization of BSK1 within the plasma membrane underlies the mechanism of signal-specific activation for growth or immunity. Resting BSK1 localizes to membrane rafts as complexes. Unlike BSK1-associated FLS2 and BRI1, flg22 or exogenous brassinosteroid (BR) treatment did not decrease BSK1 levels at the plasma membrane (PM) but rather induced BSK1 multimerization and dissociation from FLS2/BSK1 or BRI1/BSK1, respectively. Moreover, flg22-activated BSK1 translocated from membrane rafts to non-membrane-raft regions, whereas BR-activated BSK1 remained in membrane rafts. When applied together with flg22, BR suppressed various flg22-induced BSK1 activities such as BSK1 dissociation from FLS2/BSK1, BSK1 interaction with MAPKKK5, and BSK translocation together with MAPKKK5. Taken together, this study provides a unique insight into how the precise control of BSK1 spatiotemporal organization regulates the signaling specificity to balance plant growth and immunity. By using single-molecule techniques and biochemical approaches, this study demonstrates that the precise control of BSK1 spatiotemporal organization plays a pivotal role in fine-tuning the growth–defense trade-off between BRI1- and FLS2-mediated signaling. [ABSTRACT FROM AUTHOR]

Background: Down syndrome is the most common chromosomal disorder at birth and is often accompanied by structural birth defects. Current data on major structural defects in this population are limited. Methods: States and territorial population‐based surveillance programs submitted data on identified cases of Down syndrome and identified structural birth defects during 2013–2017. We estimated prevalence by program type and maternal and infant characteristics. Among programs with active case ascertainment, we estimated the prevalence of birth defects by organ system and for specific defects by maternal age (<35, ≥35) and infant sex. Results: We identified 13,376 cases of Down syndrome. Prevalence among all programs was 12.7 per 10,000 live births. Among these children, 75% had at least one reported co‐occurring birth defect diagnosis code. Among 6,210 cases identified by active programs, 66% had a cardiovascular defect with septal defects being the most common: atrial (32.5%), ventricular (20.6%), and atrioventricular (17.4%). Defect prevalence differed by infant sex more frequently than by maternal age. For example, atrioventricular septal defects were more common in female children (20.1% vs. 15.1%) while limb deficiencies were more prevalent in male children (0.4% vs. 0.1%). Conclusions: Our study provides updated prevalence estimates for structural defects, including rare defects, among children with Down syndrome using one of the largest and most recent cohorts to date. These data may aid clinical care and surveillance. [ABSTRACT FROM AUTHOR]

Background/Objectives: In this report, the National Birth Defects Prevention Network (NBDPN) examines and compares gastroschisis and omphalocele for a recent 5‐year birth cohort using data from 30 population‐based birth defect surveillance programs in the United States. Methods: As a special call for data for the 2019 NBDPN Annual Report, state programs reported expanded data on gastroschisis and omphalocele for birth years 2012–2016. We estimated the overall prevalence (per 10,000 live births) and 95% confidence intervals (CI) for each defect as well as by maternal race/ethnicity, maternal age, infant sex, and case ascertainment methodology utilized by the program (active vs. passive). We also compared distribution of cases by maternal and infant factors and presence/absence of other birth defects. Results: The overall prevalence estimates (per 10,000 live births) were 4.3 (95% CI: 4.1–4.4) for gastroschisis and 2.1 (95% CI: 2.0–2.2) for omphalocele. Gastroschisis was more frequent among young mothers (<25 years) and omphalocele more common among older mothers (>40 years). Mothers of infants with gastroschisis were more likely to be underweight/normal weight prior to pregnancy and mothers of infants with omphalocele more likely to be overweight/obese. Omphalocele was twice as likely as gastroschisis to co‐occur with other birth defects. Conclusions: This report highlights important differences between gastroschisis and omphalocele. These differences indicate the importance of distinguishing between these defects in epidemiologic assessments. The report also provides additional data on co‐occurrence of gastroschisis and omphalocele with other birth defects. This information can provide a basis for future research to better understand these defects. [ABSTRACT FROM AUTHOR]

Background: With their unique history of exposure to extensive nuclear testing between 1946 and 1958, descendants of Marshall Island residents may have underappreciated genetic abnormalities, increasing their risk of birth defects. Methods: We conducted a retrospective cohort study of resident women with at least one singleton live birth between 1997 and 2013 in northwest Arkansas using state birth certificate data linked to data from the Arkansas Reproductive Health Monitoring System, a statewide birth defects registry. We calculated unadjusted and adjusted prevalence ratios (PR) and 95% confidence intervals (CI) from modified Poisson regression analyses for non‐Hispanic (NH) whites, NH‐blacks, Hispanics and Marshallese, using NH‐whites as the reference group. Results: Of the 91,662 singleton births during the study period, 2,488 were to Marshallese women. Due to the relatively small number of Marshallese births, we could not calculate prevalence estimates for some defects. Marshallese infants had higher rates of congenital cataracts (PR = 9.3; 95% CI: 3.1, 27.9). Although the number of defects was low, Marshallese infants also had higher rates of truncus arteriosus (PR = 44.0; 95% CI: 2.2, 896.1). Conclusions: Marshallese infants may have increased risk of specific birth defects, but estimates are unstable because of small sample size so results are inconclusive. Larger population‐based studies would allow for further investigation of this potential risk among Marshallese infants. [ABSTRACT FROM AUTHOR]

The plant cell wall is an important interface for sensing pathogen attack and activating signaling pathways that promote plant immune responses. THESEUS1 (THE1) acts as a sensor of cell wall integrity that controls cell elongation during plant growth. However, no specific role for THE1 in plant defense responses has been reported. Here, we found that THE1 interacts with GUANINE EXCHANGE FACTOR4 (GEF4) and that both proteins play regulatory roles in plant resistance to the necrotrophic fungus Botrytis cinerea. Genetic analysis showed that THE1 and GEF4 function in the same genetic pathway to mediate plant defense responses. In addition, using transcriptome analysis, we identified various genes (such as defense-related, secondary metabolite-related, and transcription factor genes) that are likely downstream targets in the THE1-GEF4 signaling pathway. Our results suggest that THE1 functions as an upstream regulator of GEF4 signaling to positively regulate defense responses against B. cinerea in Arabidopsis. [ABSTRACT FROM AUTHOR]

Objective: To assess whether the severity of cases of spina bifida changed after the institution of mandatory folic acid fortification in the US.Study Design: Six active population-based birth defects programs provided data on cases of spina bifida for 1992-1996 (prefortification period) and 1999-2016 (postfortification period). The programs contributed varying years of data. Case information included both a medical record verbatim text description of the spina bifida diagnosis and spina bifida codes (International Classification of Diseases, Clinical Modification, or a modified birth defects surveillance coding system). Comparing the prefortification and postfortification periods, aORs for case severity (upper-level lesions [cervical, thoracic] vs lower-level lesions [lumbar, sacral]) and prevalence ratios (PRs) were estimated.Results: A total of 2593 cases of spina bifida (out of 7 816 062 live births) met the inclusion criteria, including 573 cases from the prefortification period and 2020 cases from the postfortification period. Case severity decreased by 70% (aOR, 0.30; 95% CI, 0.26-0.35) between the fortification periods. The decrease was most pronounced for non-Hispanic White mothers. Overall spina bifida prevalence declined by 23% (PR, 0.77; 95% CI, 0.71-0.85), with similar reductions seen across the early, mid, and recent postfortification periods. A statistically significant decrease in upper-level lesions occurred in the postfortification period compared with the prefortification period (PR, 0.28; 95% CI, 0.22-0.34), whereas the prevalence of lower-level lesions remained relatively similar (PR, 0.94; 95% CI, 0.84-1.05).Conclusions: The severity of spina bifida cases decreased after mandatory folic acid fortification in the US. Further examination is warranted to better understand the potential effect of folic acid on spina bifida severity. [ABSTRACT FROM AUTHOR]

Plant hormones are crucial signaling molecules that coordinate all aspects of plant growth, development and defense. A great deal of attention has been attracted from biologists to study the molecular mechanisms for perception and signal transduction of plant hormones during the last two decades. Tremendous progress has been made in identifying receptors and key signaling components of plant hormones. The holistic picture of hormone signaling pathways is extremely complicated, this review will give a general overview of perception and signal transduction mechanisms of auxin, gibberellin, cytokinin, abscisic acid, ethylene, brassinosteroid, and jasmonate. [ABSTRACT FROM AUTHOR]

Jasmonates (JAs) are a new class of plant hormone that regulate expression of diverse genes to mediate various plant responses. The Arabidopsis F-box protein COI1 is required for plant defense and male fertility in JA signal pathway. To further investigate the regulatory role of COI1 in male fertility, we compared the proteomics profiles of Arabidopsis wild type (WT) flowers with coi1-1 mutant male-sterile flowers using two-dimensional difference gel electrophoresis coupled with matrix-assisted laser desoption/ionization-time-of-flight mass spectrometry. Sixteen proteins with potential function in specific biological processes such as metabolism processes and defense/stress responses were differentially expressed in WT and coi1-1 mutant flowers. Verification on a phi class glutathione transferase AtGSTF9, one out of these 16 identified proteins, revealed that the expression of AtGSTF9 was severely downregulated in flowers of coi1-1 mutant compared with that of WT. Further function analyses of these genes would provide new insights into the molecular basis of COI1-regulated male fertility. [ABSTRACT FROM AUTHOR]

Aiming to construct a direct Z-scheme binary heterostructure for efficient degradation of the organic dye Rhodamine B (RhB), ZnWO4 nanorods decorated with SnS nanodots were rationally designed and prepared via a facile two-step route. Morphological observation and structural study showed that ultra-fine SnS nanodots were anchored on the surface of ZnWO4 nanorods to form an intimate contact between the two components. Such a special structure provided SnS/ZnWO4 nanocomposites with significantly enhanced light harvesting capacity, revealed by the results of UV-vis diffuse reflection spectroscopy (DRS). Photoluminescence (PL) analysis in combination with electrochemical measurements demonstrated that the recombination of photoactivated charge carriers was efficiently inhibited and the transfer of photoactivated charge carriers was successfully achieved due to the introduction of SnS. The degradation rate over SnS/ZnWO4 nanocomposites reached a maximum value at SnS content of 9 wt%. The significantly enhanced photoactivity of SnS/ZnWO4 nanocomposites was imputed to the synergistic effect of the promoted light absorption ability and effective photogenerated charge carriers' transfer and separation. [ABSTRACT FROM AUTHOR]

Lead is a heavy metal known to be toxic to both animals and plants. Nitric oxide (NO) was reported to participate in plant responses to different heavy metal stresses. In this study, we analyzed the function of exogenous and endogenous NO in Pb-induced toxicity in tobacco BY-2 cells, focusing on the role of NO in the generation of reactive oxygen species (ROS) as well as Pb2+ and Ca2+ fluxes using non-invasive micro-test technology (NMT). Pb treatment induced BY-2 cell death and rapid NO and ROS generation, while NO burst occurred earlier than ROS accumulation. The elimination of NO by 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) resulted in a decrease of ROS, and the supplementation of NO by sodium nitroprusside (SNP) caused an increased accumulation of ROS. Furthermore, the addition of exogenous NO stimulated Pb2+ influx, thus promoting Pb uptake in cells and aggravating Pb-induced toxicity in cells, whereas the removal of endogenous NO produced the opposite effect. Moreover, we also found that both exogenous and endogenous NO enhanced Pb-induced Ca2+ effluxes and calcium homeostasis disorder. These results suggest that exogenous and endogenous NO played a critical regulatory role in BY-2 cell death induced by Pb stress by promoting Pb2+ influx and accumulation and disturbing calcium homeostasis. [ABSTRACT FROM AUTHOR]

Arabidopsis heterotrimeric G proteins regulate diverse plant growth and defense processes by coupling to 7TM AtRGS1 proteins. Although G protein mutants display alterations in response to multiple plant hormones, the underlying mechanism by which G proteins participate in the regulation of hormone responses remains elusive. Here, we show that genetic disruption of Gα and Gβ subunits results in reduced sensitivity to JA treatment. Furthermore, using confocal microscopy, VA-TIRFM, and FRET-FLIM, we provide evidence that stimulation by JA induces phosphorylation- and C-terminus-dependent endocytosis of AtRGS1, which then promotes dissociation of AtRGS1 from AtGPA1. In addition, SPT analysis reveals that JA treatment affects the diffusion dynamics of AtRGS1 and AtRGS1-ΔCt. Taken together, these findings suggest that the JA signal activates heterotrimeric G proteins through the endocytosis of AtRGS1 and dissociation of AtRGS1 from AtGPA1, thus providing valuable insight into the mechanisms of how the G protein system perceives and transduces phytohormone signals. [ABSTRACT FROM AUTHOR]

Background: Esophageal atresia (EA) affects around 2.3-2.6 per 10,000 births world-wide. Infants born with this condition require surgical correction soon after birth. Most survival studies of infants with EA are locally or regionally based. We aimed to describe survival across multiple world regions., Methods: We included infants diagnosed with EA between 1980 and 2015 from 24 birth defects surveillance programs that are members of the International Clearinghouse for Birth Defects Surveillance and Research. We calculated survival as the proportion of liveborn infants alive at 1 month, 1- and 5-years, among all infants with EA, those with isolated EA, those with EA and additional anomalies or EA and a chromosomal anomaly or genetic syndrome. We also investigated trends in survival over the decades, 1980s-2010s., Results: We included 6,466 liveborn infants with EA. Survival was 89.4% (95% CI 88.1-90.5) at 1-month, 84.5% (95% CI 83.0-85.9) at 1-year and 82.7% (95% CI 81.2-84.2) at 5-years. One-month survival for infants with isolated EA (97.1%) was higher than for infants with additional anomalies (89.7%) or infants with chromosomal or genetic syndrome diagnoses (57.3%) with little change at 1- and 5-years. Survival at 1 month improved from the 1980s to the 2010s, by 6.5% for infants with isolated EA and by 21.5% for infants with EA and additional anomalies., Conclusions: Almost all infants with isolated EA survived to 5 years. Mortality was higher for infants with EA and an additional anomaly, including chromosomal or genetic syndromes. Survival improved from the 1980s, particularly for those with additional anomalies., (© 2021 Wiley Periodicals LLC.)

Lead is a heavy metal known to be toxic to both animals and plants. Nitric oxide (NO) was reported to participate in plant responses to different heavy metal stresses. In this study, we analyzed the function of exogenous and endogenous NO in Pb-induced toxicity in tobacco BY-2 cells, focusing on the role of NO in the generation of reactive oxygen species (ROS) as well as Pb 2+ and Ca 2+ fluxes using non-invasive micro-test technology (NMT). Pb treatment induced BY-2 cell death and rapid NO and ROS generation, while NO burst occurred earlier than ROS accumulation. The elimination of NO by 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) resulted in a decrease of ROS, and the supplementation of NO by sodium nitroprusside (SNP) caused an increased accumulation of ROS. Furthermore, the addition of exogenous NO stimulated Pb 2+ influx, thus promoting Pb uptake in cells and aggravating Pb-induced toxicity in cells, whereas the removal of endogenous NO produced the opposite effect. Moreover, we also found that both exogenous and endogenous NO enhanced Pb-induced Ca 2+ effluxes and calcium homeostasis disorder. These results suggest that exogenous and endogenous NO played a critical regulatory role in BY-2 cell death induced by Pb stress by promoting Pb 2+ influx and accumulation and disturbing calcium homeostasis.

The dual-affinity nitrate transceptor NITRATE TRANSPORTER1.1 (NRT1.1) has two modes of transport and signaling, governed by Thr-101 (T101) phosphorylation. NRT1.1 regulates lateral root (LR) development by modulating nitrate-dependent basipetal auxin export and nitrate-mediated signal transduction. Here, using the Arabidopsis ( Arabidopsis thaliana ) NRT1.1 T101D phosphomimetic and NRT1.1 T101A nonphosphorylatable mutants, we found that the phosphorylation state of NRT1.1 plays a key role in NRT1.1 function during LR development. Single-particle tracking revealed that phosphorylation affected NRT1.1 spatiotemporal dynamics. The phosphomimetic NRT1.1 T101D form showed fast lateral mobility and membrane partitioning that facilitated auxin flux under low-nitrate conditions. By contrast, nonphosphorylatable NRT1.1 T101A showed low lateral mobility and oligomerized at the plasma membrane (PM), where it induced endocytosis via the clathrin-mediated endocytosis and microdomain-mediated endocytosis pathways under high-nitrate conditions. These behaviors promoted LR development by suppressing NRT1.1-controlled auxin transport on the PM and stimulating Ca 2+ -ARABIDOPSIS NITRATE REGULATED1 signaling from the endosome., (© 2019 American Society of Plant Biologists. All Rights Reserved.)

Cunninghamia lanceolata (Chinese fir) is a fast-growing and commercially important conifer of the Cupressaceae family. Due to the unavailability of complete genome sequences and relatively poor genetic background information of the Chinese fir, it is necessary to identify and analyze the expression levels of suitable housekeeping genes (HKGs) as internal reference for precise analysis. Based on the results of database analysis and transcriptome sequencing, we have chosen five candidate HKGs (Actin, GAPDH, EF1a, 18S rRNA, and UBQ) with conservative sequences in the Chinese fir and related species for quantitative analysis. The expression levels of these HKGs in roots and cotyledons under five different abiotic stresses in different time intervals were measured by qRT-PCR. The data were statistically analyzed using the following algorithms: NormFinder, BestKeeper, and geNorm. Finally, RankAggreg was applied to merge the sequences generated from three programs and rank these according to consensus sequences. The expression levels of these HKGs showed variable stabilities under different abiotic stresses. Among these, Actin was the most stable internal control in root, and GAPDH was the most stable housekeeping gene in cotyledon. We have also described an experimental procedure for selecting HKGs based on the de novo sequencing database of other non-model plants.

Background: Information tracking changes of birthweight is scarce in China. To examine trends of low birthweight (birthweight < 2500 g) and macrosomia (birthweight ≥ 4000 g) and potential risk factors in Beijing, hospital records from two major obstetrics and gynecology hospitals in urban districts in Beijing were analyzed., Methods: Hospital records from 1996 to 2010 were retrieved. Information of prenatal examination and birth outcomes was entered into a structured database. Live births were used for trend analysis. Information of live births in 2010 was used to identify potential risk factors., Results: A total of 63 661 live births were delivered during 1996-2010 in the study hospitals. The average birthweight increased from 3271 g in 1996 to 3 359 g in 2000 and slightly declined to 3 331 in 2010. The percentage of low birthweight fluctuated around 4.0%. No significant increase or decrease was observed. Preterm birth was the main cause of low birthweight, accounting for more than 73% of low birthweight. The average percentage of macrosomia was 7.6%. The percentages of macrosomia increased from 6.6% in 1996 to 9.5% in 2000 and declined to 7.0% in 2010. Excessive gestational weight gain and gestational diabetes were significantly associated with macrosomia., Conclusions: Continuously monitoring abnormal birthweight is needed and intervention should focus on appropriate gestational weight gain and reduction of preterm birth and gestational diabetes.

Data about metabolic syndrome (MetS) in children is limited in China. We aimed to assess the prevalence of MetS related components, and their association with obesity. Data were collected as part of a representative study on MetS among 19593 children, aged 6-18 years old in Beijing. General obesity was assessed by body mass index (BMI) and central obesity by waist circumference. Finger capillary blood tests were used to assess triglyceride (TG), total cholesterol (TC) and impaired fasting glucose (IFG). Vein blood samples were collected from a subsample of 3814 children aged 10-18 years to classify MetS. MetS was defined according to the International Diabetes Federation 2007 definition. The associations between MetS related components and the degree and type of obesity were tested using logistic regression models. The prevalence of overweight, obesity, high blood pressure, elevated TG, TC and IFG were 13.6%, 5.8%, 8.5%, 8.8%, 1.2% and 2.5%, respectively. Compared with normal weight children, overweight and obese children were more likely to have other MetS related components. In the subsample of 3814 children aged 10-18 years, the prevalence of MetS was much higher in obese subjects than in their normal weight counterparts (27.6% vs. 0.2%). Children with both general and central obesity had the highest prevalence of MetS. Compared with normal weight children, overweight and obese children were more likely to have MetS (overweight: OR=67.33, 95%CI=21.32-212.61; obesity: OR=249.99, 95% CI=79.51-785.98). Prevalence of MetS related components has reached high level among Beijing children who were overweight or obese. The association between metabolic disorders and obesity was strong.

Jasmonates (JAs) induce leaf senescence in many plant species. The Arabidopsis F-box protein coronatine insensitive 1 (COI1) is required for various JA-regulated plant responses including plant fertility, defense responses and leaf senescence. However, the molecular basis for COI1-dependent JA-induced leaf senescence remains unknown. In our Plant Physiology paper, we identified a COI1-dependent JA-repressed protein, Rubisco activase (RCA) in Arabidopsis. Further genetic and physiological analyses showed that the COI1-dependent JA repression of RCA correlated with JA-induced leaf senescence, and that loss of RCA led to typical senescence-associated features. Therefore, we suggested that the COI1-dependent JA repression of RCA played an important role in JA-induced leaf senescence. In this addendum, we made a relatively deep discussion on RCA function in JA-induced leaf senescence and JA-mediated defense responses. We also discussed the possible role of JA in plant natural senescence.