The Glucagon-like peptide-1 receptor (GLP-1R) is a member of the class B G protein-coupled receptor (GPCR) family and a well-established target for the treatment of type 2 diabetes. The N-terminal extracellular domain (ECD) of GLP-1R is important for GLP-1 binding and the crystal structure of the GLP-1/ECD complex was reported previously. The first structure of a class B GPCR transmembrane (TM) domain was solved recently, but the full length receptor structure is still not well understood.
View Article and Find Full Text PDFProgrammable DNA nucleases such as TALENs and CRISPR/Cas9 are emerging as powerful tools for genome editing. Dual-fluorescent surrogate systems have been demonstrated by several studies to recapitulate DNA nuclease activity and enrich for genetically edited cells. In this study, we created a single-strand annealing-directed, dual-fluorescent surrogate reporter system, referred to as C-Check.
View Article and Find Full Text PDFThe Reg3 peptides INGAP-PP and human Reg3α/β (HIP) have been hypothesized to stimulate β-cell neogenesis in the pancreas. Administration of INGAP-PP has been shown to cause an increase in β-cell mass in multiple animal models, reverse streptozotocin (STZ) induced diabetes in mice and reduces HbA1c levels in type 2 diabetic humans. In this study, we have examined the ability of the INGAP-PP and HIP peptides to induce β-cell formation in vivo in normal mice through short-term administration of the peptides.
View Article and Find Full Text PDFTumor necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine involved in the pathogenesis of several diseases including type 1 diabetes mellitus (T1DM). TNFalpha in combination with interleukin-1-beta (IL-1beta) and/or interferon-gamma (IFNgamma) induces specific destruction of the pancreatic insulin-producing beta cells. Suppressor of cytokine signalling-3 (SOCS-3) proteins regulate signalling induced by a number of cytokines including growth hormone, IFNgamma and IL-1beta which signals via very distinctive pathways.
View Article and Find Full Text PDFIL-1 plays a major role in inflammation and autoimmunity through activation of nuclear factor kappa B (NFkappaB) and MAPKs. Although a great deal is known about the mechanism of activation of NFkappaB and MAPKs by IL-1, much less is known about the down-regulation of this pathway. Suppressor of cytokine signaling (SOCS)-3 was shown to inhibit IL-1-induced transcription and activation of NFkappaB and the MAPKs JNK and p38, but the mechanism is unknown.
View Article and Find Full Text PDFGH is an important regulator of cell growth and metabolism. In the pancreas, GH stimulates mitogenesis as well as insulin production in beta-cells. The cellular effects of GH are exerted mainly through activation of the Janus kinase-signal transducer and activator of transcription (STAT) pathway.
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