Human small Maf proteins form heterodimers with CNC family transcription factors and recognize the NF-E2 motif.
The transcription factor NF-E2, a heterodimeric protein complex composed of p45 and small Maf family proteins, is considered crucial for the regulation of erythroid gene expression and platelet formation. To facilitate the characterization of NF-E2 functions in human cells, we isolated cDNAs encoding two members of the small Maf family, MafK and MafG. The human mafK and mafG genes encode proteins of 156 and 162 amino acid residues, respectively, whose deduced amino acid sequences show approximately 95% identity to their respective chicken counterparts. Expression of mafK mRNA is high in heart, skeletal muscle and placenta, whereas mafG mRNA is abundant in skeletal muscle and is moderately expressed in heart and brain. Both are expressed in all hematopoietic cell lines, including those of erythroid and megakaryocytic lineages. In electrophoretic gel mobility shift assays binding to NF-E2 sites was found to depend on formation of homodimers or heterodimers with p45 and p45-related CNC family proteins. The results suggest that the small Maf family proteins function in human cells through interaction with various basic-leucine zipper-type transcription factors.
Toki
T
T
Department of Pediatrics, Hirosaki University, Japan.
Itoh
J
J
Kitazawa
J
J
Arai
K
K
Hatakeyama
K
K
Akasaka
J
J
Igarashi
K
K
Nomura
N
N
Yokoyama
M
M
Yamamoto
M
M
Ito
E
E
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D019556:COS Cells; D002460:Cell Line; D002645:Chickens; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D019281:Dimerization; D050981:Erythroid-Specific DNA-Binding Factors; D005260:Female; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D016350:Leucine Zippers; D051259:MafG Transcription Factor; D050985:MafK Transcription Factor; D051379:Mice; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D009928:Organ Specificity; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D055503:Protein Multimerization; D012333:RNA, Messenger / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012097:Repressor Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; C103944:MAFG protein, human; C494695:MAFK protein, human; D051259:MafG Transcription Factor; D050985:MafK Transcription Factor; C491247:Mafg protein, mouse; C494696:Mafk protein, mouse; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; C494692:NFE2 protein, human; C494693:Nfe2 protein, mouse; D009687:Nuclear Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012097:Repressor Proteins; D014157:Transcription Factors