Analysis of zinc-fingers and homeoboxes (ZHX)-1-interacting proteins: molecular cloning and characterization of a member of the ZHX family, ZHX3.
Human zinc-fingers and homeoboxes (ZHX) 1, a transcriptional repressor, was originally cloned as an interacting protein with the activation domain of the A subunit of nuclear factor-Y (NF-YA). As the first step in investigating the mechanism by which ZHX1 acts as a transcriptional repressor, we conducted a search of ZHX1-interacting proteins using a yeast two-hybrid system. Nuclear proteins such as ZHX1, transcriptional co-factors and DNA-binding proteins, zyxin, androgen-induced aldose reductase and eleven-nineteen lysine-rich leukaemia gene, as well as some unknown proteins, were cloned. Molecular cloning and determination of the nucleotide sequence of the full-length cDNA encoding a novel protein revealed that it consists of 956 amino acid residues and contains two zinc-finger (Znf) motifs and five homeodomains (HDs) as well as ZHX1. We concluded that the protein forms the ZHX family with ZHX1 and denoted it ZHX3. ZHX3 not only dimerizes with both ZHX1 and ZHX3, but also interacts with the activation domain of the NF-YA. Further analysis revealed that ZHX3 is a ubiquitous transcriptional repressor that is localized in nuclei and functions as a dimer. Lastly, the dimerization domain, the interaction domain with NF-YA, and the repressor domain are mapped to a region including the HD1 region, and two nuclear localization signals are mapped to the N-terminal through Znf1 and the HD2 region, respectively.
Yamada
Kazuya
K
Department of Biochemistry, Fukui Medical University, and Japan and CREST, Japan Science and Technology, Fukui 910-1193, Japan. kazuya@fmsrsa.fukui-med.ac.jp
Kawata
Hiroko
H
Shou
Zhangfei
Z
Hirano
Satoko
S
Mizutani
Tetsuya
T
Yazawa
Takashi
T
Sekiguchi
Toshio
T
Yoshino
Miki
M
Kajitani
Takashi
T
Miyamoto
Kaoru
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D023081:CCAAT-Binding Factor / Q000378:metabolism; D003001:Cloning, Molecular; D017931:DNA Primers; D019281:Dimerization; D005784:Gene Amplification; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D005810:Multigene Family; D012333:RNA, Messenger / Q000235:genetics; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013737:Testis / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D016335:Zinc Fingers
D023081:CCAAT-Binding Factor; D017931:DNA Primers; D018398:Homeodomain Proteins; C492061:NFYA protein, human; C492060:Nfya protein, mouse; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; C484404:ZHX1 protein, human; C476878:ZHX3 protein, human