title: ISL1 physically interacts with BETA2 to promote insulin gene transcriptional synergy in non-beta cells.
abstract: ISL1 is a LIM homeodomain protein that plays an important role in insulin gene transcriptional activation and islet cell formation. BETA2 is a transcription factor in the basic helix-loop-helix (bHLH) family, which activates expression of tissue-specific genes in several developmental systems. In this study, we investigated the functional and physical interactions of ISL1 and BETA2 in promoting insulin gene transcription in non-beta cells. Using the luciferase assay, we demonstrated that ISL1 and BETA2 could activate insulin gene transcription synergistically. Co-immunoprecipitation also supported that ISL1 and BETA2 appear in one complex and this physical interaction mediates the synergy between these two proteins.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University, Beijing 100083, China.
authors.forename: Si-Yang
authors.initials: SY
authors.lastname: Peng
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Meng
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.forename: Kang-Tao
authors.initials: KT
authors.lastname: Ma
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Zhou
mesh_terms: D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000235:genetics* / Q000378:metabolism; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding / Q000235:genetics / Q000502:physiology*; D011994:Recombinant Proteins; D014157:Transcription Factors; D014158:Transcription, Genetic / Q000502:physiology*; D014162:Transfection
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D007328:Insulin; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D014157:Transcription Factors; C093970:NEUROD1 protein, human; C063843:insulin gene enhancer binding protein Isl-1