Diabetes 57:654-668, 2008 DOI: 10.2337/db07-1362 © 2008 by the American Diabetes Association
Defining Pancreatic Endocrine Precursors and Their Descendants
1 Department of Genetics and Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania Address correspondence and reprint requests to Klaus H. Kaestner, PhD, University of Pennsylvania, Medical School, Department of Genetics, 415 Curie Blvd., Philadelphia, PA 19104. E-mail: kaestner{at}mail.med.upenn.edu
Key Words: bHLH, basic helix-loop-helix EDGE, Extraction of Differential Gene Expression EGFP, enhanced green fluorescent protein GO, gene ontology HLH, helix-loop-helix qRT-PCR, quantitative real-time RT-PCR
OBJECTIVE—The global incidence of diabetes continues to increase. Cell replacement therapy and islet transplantation offer hope, especially for severely affected patients. Efforts to differentiate insulin-producing β-cells from progenitor or stem cells require knowledge of the transcriptional programs that regulate the development of the endocrine pancreas. RESEARCH DESIGN AND METHODS—Differentiation toward the endocrine lineage is dependent on the transcription factor Neurogenin 3 (Neurog3, Ngn3). We utilize a Neurog3–enhanced green fluorescent protein knock-in mouse model to isolate endocrine progenitor cells from embryonic pancreata (embryonic day [E]13.5 through E17.5). Using advanced genomic approaches, we generate a comprehensive gene expression profile of these progenitors and their immediate descendants. RESULTS—A total of 1,029 genes were identified as being temporally regulated in the endocrine lineage during fetal development, 237 of which are transcriptional regulators. Through pathway analysis, we have modeled regulatory networks involving these proteins that highlight the complex transcriptional hierarchy governing endocrine differentiation. CONCLUSIONS—We have been able to accurately capture the gene expression profile of the pancreatic endocrine progenitors and their descendants. The list of temporally regulated genes identified in fetal endocrine precursors and their immediate descendants provides a novel and important resource for developmental biologists and diabetes researchers alike.
|
|
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||