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La investigación se ejecutó en la Finca Experimental “La María” propiedad de la Univer-sidad Técnica Estatal de Quevedo (UTEQ) localizada en el km 71/2de la vía Quevedo-Mocache; Provincia de Los Ríos cuya ubicación geográfica de 1º 6’ 23” de latitud sury 79º 29’ 12” de longitud oeste y a una altura de 73 m.s.n.m. El objetivo principal fueevaluar el comportamiento productivo de cuyes con la inclusión del 20% de harinasderivadas de follajes arbustivos y arbóreos tropicales. Se utilizaron 40 cuyes macho de 30días de edad. Se empleó un diseño completamente al azar con cinco tratamientos, cuatroréplicas y la unidad experimental estuvo conformado por dos cuyes. Para determinarlas diferencias entre medias de tratamientos se aplicó la prueba de Tukey (P≤0.05). Seevaluaron cinco dietas-tratamientos: (T0) dieta 100% balanceado, (T1) 80% dieta y 20%harina deMorus alba, (T2) 80% dieta y 20% harina deErythrina poeppigiana, (T3) 80%dieta y 20% harina deTithonia diversifolia, (T4) 80% dieta y 20% harina deHibiscusrosa-sinensis. Las variables bajo estudio fueron: consumo de alimento de balanceado enmateria seca (CABMS, g), ganancia de peso (GP, g), índice de conversión alimenticia(ICA) y rendimiento en canal (RC, %). La rentabilidad de los tratamientos se determinóa través de la relación beneficio-costo (R b/c). Los mayores (P

Aquaculture is still in early development in Madagascar and Tanzania, while in Indonesia, aquaculture has a long history. In Madagascar, villagers are farming seaweed and sea cucumbers, as part of small-scale community-based aquaculture (CBA). They followed a contractual model between a private farming company and farmers. Local non-governmental organisations (NGOs) and public institutions in Madagascar jointly strive to reverse the trend of ongoing anthropogenic coastal degradation. In Tanzania, the cultivation of red seaweeds has been established for over 30 years, with declining production attributed to climate change. While shrimp farming still involves, to some extent, clearing of mangroves in Tanzania, seaweed culture has only mild impact on coastal ecosystems. Farming areas provide shelter and habitat for juvenile fish, crabs and other organisms. Therefore, NGOs ask for support to improve culture methods. Various problems and shortcomings in Indonesia have been clearly identified, including issues related to new aquaculture areas, pollutants, emerging diseases, insufficient broodstock and fry supply, as well as a lack of technology and manpower. To address these challenges and ensure the growth of aquaculture production, the government has implemented national policies and established training and broodstock centers throughout the country. In Madagascar, the CBA programme stands out as a success story and can serve as a template for other coastal regions and countries. In Tanzania, the adoption of CBA model for co-culture could be the future. In Indonesia, due to a very long coastlines and complicated legislation, IMTA seems to be particularly suitable, as successfully tested in model regions. [ABSTRACT FROM AUTHOR]

SNX32 is a member of the evolutionarily conserved Phox (PX) homology domain- and Bin/Amphiphysin/Rvs (BAR) domain- containing sorting nexin (SNX-BAR) family of proteins, which play important roles in sorting and membrane trafficking of endosomal cargoes. Although SNX32 shares the highest amino acid sequence homology with SNX6, and has been believed to function redundantly with SNX5 and SNX6 in retrieval of the cation-independent mannose-6-phosphate receptor (CI-MPR) from endosomes to the trans-Golgi network (TGN), its role(s) in intracellular protein trafficking remains largely unexplored. Here, we report that it functions in parallel with SNX1 in mediating epidermal growth factor (EGF)-stimulated postendocytic trafficking of the epidermal growth factor receptor (EGFR). Moreover, SNX32 interacts directly with EGFR, and recruits SNX5 to promote sorting of EGF-EGFR into multivesicular bodies (MVBs) for lysosomal degradation. Thus, SNX32 functions distinctively from other SNX-BAR proteins to mediate signaling-coupled endolysosomal trafficking of EGFR., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The transcriptome is the complete set of transcripts in a cell or tissue and includes ribosomal RNA (rRNA), messenger RNA (mRNA), transfer RNA (tRNA), and regulatory noncoding RNA. At steady-state, the transcriptome results from a compensatory variation of the transcription and decay rate to maintain the RNA concentration constant. RNA transcription constitutes the first stage in gene expression, and thus is a major and primary mode of gene expression control. Nevertheless, regulation of RNA decay is also a key factor in gene expression control, involving either selective RNA stabilization or enhanced degradation. Transcriptome analysis allows the identification of gene expression alterations, providing new insights regarding the pathways and mechanisms involved in physiological and pathological processes. Upon perturbation of cell homeostasis, rapid changes in gene expression are required to adapt to new conditions. Thus, to better understand the regulatory mechanisms associated with gene expression alterations, it is vital to acknowledge the relative contribution of RNA synthesis and decay to the transcriptome. To the toxicology field, the study of gene expression regulation mechanisms can help identify the early and mechanistic relevant cellular events associated with a particular response. This review aims to provide a critical comparison of the available methods used to analyze the contribution of RNA transcription and decay to gene expression dynamics. Notwithstanding, an integration of the data obtained is necessary to understand the entire repercussions of gene transcription changes at a system-level. Thus, a brief overview of the methods available for the integration and analysis of the data obtained from transcriptome analysis will also be provided. [ABSTRACT FROM AUTHOR]

Objective: Postprandial hypotension (PPH) is a common phenomenon among older adults. The degree to which individuals experience PPH is related to cerebrovascular risk factors and the presence of neurodegenerative diseases such as Alzheimer's disease (AD). Carrier status of the E4 allele of the apolipoprotein E (APOE) gene is a risk factor for AD and influences a variety of responses to metabolic and dietary interventions. However, it is unknown whether APOE genotype influences the risk of PPH and whether type of meal can mediate that response. Design: Acute meal study with a crossover design. Participants: 32 cognitively healthy older adults with (n=18) and without (n=14) E4+ carrier status. Intervention: As a part of an ongoing meal study we examined the postprandial blood pressure response after ingestion of a high carbohydrate (HCM) and high fat meal (HFM). Measurements: Blood pressure measurements were taken at 7 time points and change scores, area under the curve (AUC) scores were calculated. Data were analyzed by repeated measures ANOVA as well as Pearson correlation. Results: Both meals produced a sustained drop in systolic (SBP) and diastolic (DBP) blood pressure, with 37.5% of participants meeting criteria for PPH. Participants carrying the E4+ risk gene experienced a larger decrease in SBP than E4- participants, and this was significantly different after the HFM (E4+ AUC = -30.8 ± 7.6, E4- AUC = -0.2 ± 8.7, p=0.015). Increasing age was associated with a larger drop in postprandial blood pressure but only for the E4+ group after the HFM (p=0.002). Conclusions: These data suggest that E4+ individuals experience a greater postprandial blood pressure response particularly following high fat feeding, and this effect becomes more pronounced with age. The prevalence of PPH may play a role in the development of AD and may be mediated by diet. [ABSTRACT FROM AUTHOR]

The poor or lack of injured adult central nervous system (CNS) axon regeneration results in devastating consequences and poor functional recovery. The interplay between the intrinsic and extrinsic factors contributes to robust inhibition of axon regeneration of injured CNS neurons. The insufficient or lack of trophic support for injured neurons is considered as one of the major obstacles contributing to their failure to survive and regrow their axons after injury. In the CNS, many of the signalling pathways associated with neuronal survival and axon regeneration are regulated by several classes of receptor tyrosine kinases (RTK) that respond to a variety of ligands. This paper highlights and summarises the most relevant recent findings pertinent to different classes of the RTK family of molecules, with a particular focus on elucidating their role in CNS axon regeneration. [ABSTRACT FROM AUTHOR]

Heterotrimeric GTP- binding proteins (G proteins) control cellular functions by transducing signals from the outside to the inside of cells. Regulator of G protein signaling (RGS) proteins are key modulators of the amplitude and duration of G protein-mediated signaling through their ability to serve as guanosine triphosphatase-activating proteins (GAPs). We have identified RGS-PX1, a [Gα.sub.s]-specific GAP. The RGS domain of RGS-PX1 specifically interacted with [Gα.sub.s], accelerated its GTP hydrolysis, and attenuated [Gα.sub.s]-mediated signaling. RGS-PX1 also contains a Phox (PX) domain that resembles those in sorting nexin (SNX) proteins. Expression of RGS-PX1 delayed lysosomal degradation of the EGF receptor. Because of its bifunctional role as both a GAP and a SNX, RGS-PX1 may link heterotrimeric G protein signaling and vesicular trafficking., Heterotrimeric G proteins relay extracellular signals initiated by hormones, neurotransmitters, chemokines, and sensory stimuli through G protein-coupled receptors to intracellular effectors and trigger a variety of physiological responses (1, 2). [...]

Phosphoinositide (PI)--binding domains play critical roles in the intracellular localization of a variety of cell-signaling proteins. The 120--amino acid Phox homology (PX) domain targets proteins to organelle membranes through interactions between two conserved basic motifs within the PX domain and specific PIs. The combination of protein-lipid and protein-protein interactions ensures the proper localization and regulation of PX domain--containing proteins. Upon proper localization, PX domain--containing proteins can then bind to additional proteins and execute their functions in a diverse set of biological pathways, including intracellular protein transport, cell growth and survival cytoskeletal organization, and neutrophil defense., With 30,000 to 40,000 genes potentially expressed in the human genome, cells face the difficult task of assembling these gene products into functional complexes and localizing them to appropriate sites. [...]

Epidermal growth factor receptor (EGFR) signaling was analyzed in mammalian cells conditionally defective for receptor-mediated endocytosis. EGF-dependent cell proliferation was enhanced in endocytosis-defective cells. However, early EGF-dependent signaling events were not uniformly up-regulated. A subset of signal transducers required the normal endocytic trafficking of EGFR for full activation. Thus, endocytic trafficking of activated EGFR plays a critical role not only in attenuating EGFR signaling but also in establishing and controlling specific signaling pathways., Signaling by ligand-activated receptor tyrosine kineses (RTKs) such as EGFR can elicit a wide range of cell type-specific responses leading to proliferation or differentiation. EGF binling triggers dimerization and trans- [...]

Yeast RNA polymerase II initiation factor b copurifies with three polypeptides of 85, 73, and 50 kilodaltons and with a protein kinase that phosphorylates the carboxyl-terminal repeat domain (CTD) of the largest polymerase subunit. The gene that encodes the 73-kilodalton polypeptide, designated TFB1, was cloned and found to be essential for cell growth. The deduced protein sequence exhibits no similarity to those of protein kinases. However, the sequence is similar to that of the 62-kilodalton subunit of the HeLa transcription factor BTF2, suggesting that this factor is the human counterpart of yeast factor b. Immunoprecipitation experiments using antibodies to the TFB1 gene product demonstrate that the transcriptional and CTD kinase activities of factor b are closely associated with an oligomer of the three polypeptides. Photoaffinity labeling with 3'-O-(4-benzoyl)benzoyl)-ATP (adenosine triphosphate) identified an ATP-binding site in the 85-kilodalton polypeptide, suggesting that the 85-kilodalton subunit contains the catalytic domain of the kinase., Initiation of transcription by RNA polymerase II requires several accessory protein factors whose roles remain, for the most part, to be elucidated. Recognition of the TATA element of a promoter [...]

Most neurotransmitters, hormones, and growth factors activate cellular signaling pathways by binding to specific membrane receptors. These signaling pathways subsequently modulate biochemical networks comprising various cytoplasmic kinases, phosphatases, and guanosine [...]

The vectorial movement of proteins requires specific recognition by components of the vesicular trafficking machinery. A protein, sorting nexin-1 (SNX1), was identified in a human cell line that bound to a region of the epidermal growth factor receptor (EGFR) containing the lysosomal targeting code. SNX1 contains a region of homology to a yeast vacuolar sorting protein, and overexpression of SNX1 decreased the amount of EGFR on the cell surface as a result of enhanced rates of constitutive and ligand-induced degradation. Thus, SNX1 is likely to play a role in sorting EGFR to lysosomes., Ligand-activated growth factor and nutrient receptors are internalized by coated pits and transported together to endosomes. The task of segregating receptors destined for lysosomal degradation (such as EGFR) from those [...]