Defining pancreatic endocrine precursors and their descendants.
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 beta-cells from progenitor or stem cells require knowledge of the transcriptional programs that regulate the development of the endocrine pancreas.


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.
White
Peter
P
University of Pennsylvania, Medical School, Department of Genetics, Institute for Diabetes, Obesity and Metabolism, 415 Curie Blvd., Philadelphia, PA 19104, USA.
May
Catherine Lee
CL
Lamounier
Rodrigo N
RN
Brestelli
John E
JE
Kaestner
Klaus H
KH
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics* / Q000378:metabolism*; D016000:Cluster Analysis; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D008297:Male; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism*; D010179:Pancreas / Q000196:embryology* / Q000378:metabolism*; D013234:Stem Cells
D051792:Basic Helix-Loop-Helix Proteins; D009419:Nerve Tissue Proteins; C407737:Neurog3 protein, mouse