title: Contrasting patterns of expression of transcription factors in pancreatic alpha and beta cells.
abstract: Pancreatic alpha and beta cells are derived from the same progenitors but play opposing roles in the control of glucose homeostasis. Disturbances in their function are associated with diabetes mellitus. To identify many of the proteins that define their unique pathways of differentiation and functional features, we have analyzed patterns of gene expression in alphaTC1.6 vs. MIN6 cell lines by using oligonucleotide microarrays. Approximately 9-10% of >11,000 transcripts examined showed significant differences between the two cell types. Of >700 known transcripts enriched in either cell type, transcription factors and their regulators (TFR) was one of the most significantly different categories. Ninety-six members of the basic zipper, basic helix-loop-helix, homeodomain, zinc finger, high mobility group, and other transcription factor families were enriched in alpha cells; in contrast, homeodomain proteins accounted for 51% of a total of 45 TFRs enriched in beta cells. Our analysis thus highlights fundamental differences in expression of TFR subtypes within these functionally distinct islet cell types. Interestingly, the alpha cells appear to express a large proportion of factors associated with progenitor or stem-type cells, perhaps reflecting their earlier appearance during pancreatic development. The implications of these findings for a better understanding of alpha and beta cell dysfunction in diabetes mellitus are also considered.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Gene
authors.initials: G
authors.lastname: Webb
authors.forename: Yun
authors.initials: Y
authors.lastname: Cao
authors.forename: Donald F
authors.initials: DF
authors.lastname: Steiner
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology*; D007515:Islets of Langerhans / Q000166:cytology / Q000502:physiology*; D016350:Leucine Zippers; D051379:Mice; D018345:Mice, Knockout; D018075:RNA, Complementary / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics*; D016335:Zinc Fingers
chemical_list: D018075:RNA, Complementary; D014157:Transcription Factors