title: Small Maf proteins (MafF, MafG, MafK): History, structure and function.
abstract: The small Maf proteins (sMafs) are basic region leucine zipper (bZIP)-type transcription factors. The basic region of the Maf family is unique among the bZIP factors, and it contributes to the distinct DNA-binding mode of this class of proteins. MafF, MafG and MafK are the three vertebrate sMafs, and no functional differences have been observed among them in terms of their bZIP structures. sMafs form homodimers by themselves, and they form heterodimers with cap 'n' collar (CNC) proteins (p45 NF-E2, Nrf1, Nrf2, and Nrf3) and also with Bach proteins (Bach1 and Bach2). Because CNC and Bach proteins cannot bind to DNA as monomers, sMafs are indispensable partners that are required by CNC and Bach proteins to exert their functions. sMafs lack the transcriptional activation domain; hence, their homodimers act as transcriptional repressors. In contrast, sMafs participate in transcriptional activation or repression depending on their heterodimeric partner molecules and context. Mouse genetic analyses have revealed that various biological pathways are under the regulation of CNC-sMaf heterodimers. In this review, we summarize the history and current progress of sMaf studies in relation to their partners.
authors.affiliation: Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Japan. Electronic address: kfumiki@med.tohoku.ac.jp.
authors.forename: Fumiki
authors.initials: F
authors.lastname: Katsuoka
authors.affiliation: Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Japan; Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins; D004194:Disease; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D051260:MafF Transcription Factor / Q000737:chemistry / Q000235:genetics / Q000266:history / Q000502:physiology*; D051259:MafG Transcription Factor / Q000737:chemistry / Q000235:genetics / Q000266:history / Q000502:physiology*; D050985:MafK Transcription Factor / Q000737:chemistry / Q000235:genetics / Q000266:history / Q000502:physiology*; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D051260:MafF Transcription Factor; D051259:MafG Transcription Factor; D050985:MafK Transcription Factor; C484146:Maff protein, mouse; C491247:Mafg protein, mouse; C494696:Mafk protein, mouse; D009687:Nuclear Proteins; D012097:Repressor Proteins; D004247:DNA
keywords: MafF; MafG; MafK; Small Maf; bZIP transcription factor