Whitleytemple5438

Both myristoylated and non-myristoylated GCAP2 bind Ca2+ with high affinity. At odds with GCAP1 and independently of myristoylation, human GCAP2 does not significantly activate retinal GC1 in a Ca2+-dependent fashion. The IRD-associated G157R variant is characterized by a partly misfolded, molten globule-like conformation with reduced affinity for cations, and is prone to form aggregates, likely mediated by hydrophobic interactions. Our findings suggest that GCAP2 in human photoreceptors might be mostly implicated in processes other than phototransduction, and suggest a possible molecular mechanism for G157R-associated IRD.Human phosphoglycerate mutase (dPGM) catalysis is dependent on a 2,3-bisphosphoglycerate cofactor, while the nonhomologous isozyme in many parasitic species is cofactor-independent (iPGM). This mechanistic and phylogenetic diversity offers an opportunity for selective pharmacologic targeting of glycolysis in disease-causing organisms. We previously discovered ipglycermide, a potent inhibitor of iPGM, from a large combinatorial cyclic peptide library. To fully delineate the ipglycermide pharmacophore, herein we construct a detailed structure-activity relationship using 280 substituted ipglycermide analogs. Binding affinities of these analogs to immobilized C. elegans iPGM, measured as fold-enrichment relative to the index residue by deep sequencing of an mRNA display library, illuminated the significance of each amino acid to the pharmacophore. Using co-crystal structures and binding kinetics, we show that the high affinity of ipglycermide for iPGM orthologs, from B. malayi, O. volvulus, D. immitis, and E. coli is achieved by a co-dependence between 1) the off-rate mediated by the macrocycle Cys14 thiolate coordination to an active-site Zn2+ ion in the iPGM phosphatase domain, and 2) shape-complementarity surrounding the macrocyclic core at the phosphotransferase-phosphatase domain interface. Our results show that the high affinity binding of ipglycermide to iPGMs freezes these structurally dynamic enzymes into an inactive, stable complex.Excessive sugar consumption is a contributor to the worldwide epidemic of cardiometabolic disease. Understanding mechanisms by which sugar is sensed and regulates metabolic processes may provide new opportunities to prevent and treat these epidemics. Carbohydrate Responsive-Element Binding Protein (ChREBP) is a sugar sensing transcription factor that mediates genomic responses to changes in carbohydrate abundance in key metabolic tissues. Carbohydrate metabolites activate the canonical form of ChREBP, ChREBP-alpha, which stimulates production of a potent, constitutively active ChREBP isoform called ChREBP-beta. Carbohydrate metabolites and other metabolic signals may also regulate ChREBP activity via post-translational modifications including phosphorylation, acetylation, and O-GlcNAcylation that can affect ChREBP's cellular localization, stability, binding to co-factors, and transcriptional activity. In this review, we discuss mechanisms regulating ChREBP activity and highlight phenotypes and controversies in ChREBP gain- and loss-of-function genetic rodent models focused on the liver and pancreatic islets.Bacterial cell and chloroplast division are driven by a contractile "Z ring" composed of the tubulin-like cytoskeletal GTPase FtsZ. Unlike bacterial Z rings, which consist of a single FtsZ, the chloroplast Z ring in plants is composed of two FtsZ proteins, FtsZ1 and FtsZ2. Both are required for chloroplast division in vivo, but their biochemical relationship is poorly understood. We used GTPase assays, light scattering, TEM, and sedimentation assays to investigate the assembly behavior of purified Arabidopsis thaliana (At) FtsZ1 and AtFtsZ2 both individually and together. Both proteins exhibited GTPase activity. AtFtsZ2 assembled relatively quickly, forming protofilament bundles that were exceptionally stable, as indicated by their sustained assembly and slow disassembly. AtFtsZ1 did not form detectable protofilaments on its own. When mixed with AtFtsZ2, AtFtsZ1 reduced the extent and rate of AtFtsZ2 assembly, consistent with its previously demonstrated ability to promote protofilament subunit turnover in living cells. Mixing the two FtsZ proteins did not increase the overall GTPase activity, indicating that the effect of AtFtsZ1 on AtFtsZ2 assembly was not due to a stimulation of GTPase activity. However, the GTPase activity of AtFtsZ1 was required to reduce AtFtsZ2 assembly. Truncated forms of AtFtsZ1 and AtFtsZ2 consisting of only their conserved core regions largely recapitulated the behaviors of the full-length proteins. Our in vitro findings provide evidence that FtsZ1 counterbalances the stability of FtsZ2 filaments in the regulation of chloroplast Z-ring dynamics, and suggest that restraining FtsZ2 self-assembly is a critical function of FtsZ1 in chloroplasts.Background Retention can be difficult in longitudinal trials, especially among minoritized groups and individuals with low socioeconomic status (SES) who may experience more barriers to research participation. Organized retention strategies may help; however, limited research has reported on this in detail. Methods We employed several strategies throughout a 15-month randomized controlled trial to encourage retention among a diverse sample of adults with type 2 diabetes. Participants were randomized to receive mobile health support for diabetes self-care for 12 months or an attention control. Participants completed assessments at 3, 6, 12, and 15 months post-baseline. We used three main categories of retention strategies flexibility in participation (e.g., multiple methods for data collection), communication (e.g., tracking contacts), and community building (e.g., study branding, newsletters). We monitored participants' use of strategies and examined associations between participant characteristics and retention. Results Retention remained high (≥90%) at each follow-up assessment. Participants used various methods for survey completion online (34%), in-person (31%), and mail (30%). Tetramisole Most (73%) used a mail-in A1c kit at least once. Multiple completion methods were important for retaining minoritized and lower SES participants who completed assessments in-person more frequently. Communication also facilitated retention; 39% of participants used a study Helpline and tracking systems helped maintain contact. Conclusions Retaining disadvantaged patients in clinical trials is necessary so findings generalize to and can benefit these populations. Retention strategies that reduce barriers to participation and engage participants and community partners can be successful. Future studies should assess the impact of retention strategies.