Involvement of the Polycomb-group gene Ring1B in the specification of the anterior-posterior axis in mice.
The products of the Polycomb group of genes form complexes that maintain the state of transcriptional repression of several genes with relevance to development and in cell proliferation. We have identified Ring1B, the product of the Ring1B gene (Rnf2 - Mouse Genome Informatics), by means of its interaction with the Polycomb group protein Mel18. We describe biochemical and genetic studies directed to understand the biological role of Ring1B. Immunoprecipitation studies indicate that Ring1B form part of protein complexes containing the products of other Polycomb group genes, such as Rae28/Mph1 and M33, and that this complexes associate to chromosomal DNA. We have generated a mouse line bearing a hypomorphic Ring1B allele, which shows posterior homeotic transformations of the axial skeleton and a mild derepression of some Hox genes (Hoxb4, Hoxb6 and Hoxb8) in cells anterior to their normal boundaries of expression in the mesodermal compartment. By contrast, the overexpression of Ring1B in chick embryos results in the repression of Hoxb9 expression in the neural tube. These results, together with the genetic interactions observed in compound Ring1B/Mel18 mutant mice, are consistent with a role for Ring1B in the regulation of Hox gene expression by Polycomb group complexes.
Department of Molecular Embryology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan.
Maki
M
Suzuki
Yoko
Y
Mizutani-Koseki
Yu-Ichi
Y
Fujimura
Hiro
H
Miyagishima
Tomomi
T
Kaneko
Yuki
Y
Takada
Takeshi
T
Akasaka
Hideki
H
Tanzawa
Yoshihiro
Y
Takihara
Megumi
M
Nakano
Hiroshi
H
Masumoto
Miguel
M
Vidal
Kyo-Ichi
K
Isono
Haruhiko
H
Koseki
D000483:Alleles; D000818:Animals; D002843:Chromatin / Q000502:physiology; D003433:Crosses, Genetic; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D005982:Glutathione Transferase / Q000235:genetics; D006720:Homozygote; D051379:Mice; D018345:Mice, Knockout; D010641:Phenotype; D063150:Polycomb Repressive Complex 1; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D016335:Zinc Fingers
D002843:Chromatin; D017931:DNA Primers; D004268:DNA-Binding Proteins; C066476:Pcgf6 protein, mouse; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D063150:Polycomb Repressive Complex 1; D005982:Glutathione Transferase