RYBP, a new repressor protein that interacts with components of the mammalian Polycomb complex, and with the transcription factor YY1.
The products of the Polycomb group (PcG) of genes are necessary for the maintenance of transcriptional repression of a number of important developmental genes, including the homeotic genes. A two-hybrid screen was used to search for putative new members of the PcG of genes in mammals. We have identified a new Zn finger protein, RYBP, which interacts directly with both Ring1 proteins (Ring1A and Ring1B) and with M33, two mutually interacting sets of proteins of the mammalian Polycomb complex. Ring1 binds RYBP and M33 through the same C-terminal domain, whereas the RYBP-M33 interaction takes place through an M33 domain not involved in Ring1 binding. RYBP also interacts directly with YY1, a transcription factor partially related to the product of the Drosophila pleiohomeotic gene. In addition, we show here that RYBP acts as a transcriptional repressor in transiently transfected cells. Finally, RYBP shows a dynamic expression pattern during embryogenesis which initially overlaps partially that of Ring1A in the central nervous system, and later becomes ubiquitous. Taken together, these data suggest that RYBP may play a relevant role in PcG function in mammals.
García
E
E
Centro de Investigaciones Biológicas, Department of Developmental and Cell Biology, Velázquez 144, 28006 Madrid, Spain.
Marcos-Gutiérrez
C
C
del Mar Lorente
M
M
Moreno
J C
JC
Vidal
M
M
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002490:Central Nervous System / Q000196:embryology / Q000378:metabolism; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000378:metabolism; D050981:Erythroid-Specific DNA-Binding Factors; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D063150:Polycomb Repressive Complex 1; D063146:Polycomb-Group Proteins; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017384:Sequence Deletion; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics; D044767:Ubiquitin-Protein Ligases; D050986:YY1 Transcription Factor; D015003:Yeasts / Q000235:genetics; D016335:Zinc Fingers
C570426:Cbx2 protein, mouse; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D063146:Polycomb-Group Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; C120616:Rybp protein, mouse; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; C494699:Yy1 protein, mouse; D063150:Polycomb Repressive Complex 1; C080355:RING1 protein, human; C489841:RNF2 protein, human; C489840:Ring1 protein, mouse; C489842:Rnf2 protein, mouse; D044767:Ubiquitin-Protein Ligases