Document Detail

Pax6 Is Crucial for β-Cell Function, Insulin Biosynthesis, and Glucose-Induced Insulin Secretion.
MedLine Citation:
PMID:  22403172     Owner:  NLM     Status:  Publisher    
The Pax6 transcription factor is crucial for endocrine cell differentiation and function. Indeed, mutations of Pax6 are associated with a diabetic phenotype and a drastic decrease of insulin-positive cell number. Our aim was to better define the β-cell Pax6 transcriptional network and thus provide further information concerning the role of Pax6 in β-cell function. We developed a Pax6-deficient model in rat primary β-cells with specific small interfering RNA leading to a 75% knockdown of Pax6 expression. Through candidate gene approach, we confirmed that Pax6 controls the mRNA levels of the insulin 1 and 2, Pdx1, MafA, GLUT2, and PC1/3 genes in β-cells. Importantly, we identified new Pax6 target genes coding for GK, Nkx6.1, cMaf, PC2, GLP-1R and GIPR which are all involved in β-cell function. Furthermore, we demonstrated that Pax6 directly binds and activates specific elements on the promoter region of these genes. We also demonstrated that Pax6 knockdown led to decreases in insulin cell content, in insulin processing, and a specific defect of glucose-induced insulin secretion as well as a significant reduction of GLP-1 action in primary β-cells. Our results strongly suggest that Pax6 is crucial for β-cells through transcriptional control of key genes coding for proteins that are involved in insulin biosynthesis and secretion as well as glucose and incretin actions on β-cells. We provide further evidence that Pax6 represents a key element of mature β-cell function.
Yvan Gosmain; Liora S Katz; Mounia Heddad Masson; Claire Cheyssac; Caroline Poisson; Jacques Philippe
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2012-3-8
Journal Detail:
Title:  Molecular endocrinology (Baltimore, Md.)     Volume:  -     ISSN:  1944-9917     ISO Abbreviation:  -     Publication Date:  2012 Mar 
Date Detail:
Created Date:  2012-3-9     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8801431     Medline TA:  Mol Endocrinol     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Diabetes Unit, Division of Endocrinology, Diabetes, and Nutrition, University Hospital, University of Geneva Medical School, 1211 Geneva 14, Switzerland.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Placement of marker coils at biopsy: usefulness in the localization of poorly visualized renal neopl...
Next Document:  Absence of myocardial thyroid hormone inactivating deiodinase results in restrictive cardiomyopathy ...