Alternative titles; symbols
HGNC Approved Gene Symbol: RNF2
Cytogenetic location: 1q25.3 Genomic coordinates (GRCh38): 1:185,045,558-185,102,603 (from NCBI)
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 1q25.3 | Luo-Schoch-Yamamoto syndrome | 619460 | Autosomal dominant | 3 |
Polycomb group (PcG) proteins form multiprotein complexes involved in the transcriptional repression of developmentally regulated genes. RNF2 is a PcG protein that possesses ubiquitin ligase (E3) activity (Suzuki et al., 2002; Wang et al., 2004).
Using a yeast 2-hybrid screen with the ubiquitin-conjugating (E2) enzyme huntingtin-interacting protein-2 (HIP2; 602846) as bait, Lee et al. (2001) identified several RING finger motif-containing proteins, including RNF2, which they called HIPI3. The predicted 337-amino acid RNF2 protein contains a C3HC4 RING finger motif with a 12-amino acid separation between the second and third cysteines.
Tuckfield et al. (2002) isolated RNF2, which they called DING, from an erythroleukemia cell line cDNA library using a yeast 2-hybrid screen with human CP2 (TFCP2; 189889), a member of the grainyhead-like family of transcription factors, as bait.
Gross (2021) mapped the RNF2 gene to chromosome 1q25.3 based on an alignment of the RNF2 sequence (GenBank AF141327) with the genomic sequence (GRCh38).
Using GST binding assays, Lee et al. (2001) confirmed that RNF2 interacts with HIP2. In vitro ubiquitination assays showed that RNF2 has E2-dependent E3 ligase activity. Mutation analysis indicated that the N-terminal RING finger domain of RNF2 interacts with HIP2 and is necessary for the E3 ligase activity.
Using in vitro and cellular assays, Tuckfield et al. (2002) confirmed that DING interacts with CP2. Mutation analysis determined that DING interacts with CP2 and LBP1A (UBP1) through its C-terminal portion, outside the RING domain. In vitro transcription and luciferase reporter analysis showed that DING acts as repressor of CP2-dependent transcriptional activation.
Using yeast 2-hybrid analysis, Suzuki et al. (2002) found that mouse Mel18 (ZNF144; 600346) bound Ring1b and Edr2 (602979), but not Ring1a (RING1; 602045), Bmi1 (164831), or itself. GST pull-down analysis indicated that the strongest interaction was between Mel18 and the N terminus of Ring1b. Immunofluorescence microscopy demonstrated colocalization of endogenous RING1B with MEL18, BMI1, RING1A, and EDR1 (602978) in subnuclear speckles, termed PcG bodies, in interphase nuclei of human osteosarcoma cells. In addition, endogenous RING1B colocalized with exogenous Edr2 in these cells. Agarose gel electrophoresis and Western blot analysis showed that Ring1b, along with Edr1 and M33 (CBX2; 602770), associated with chromosomal DNA, but not with chromatin. The association of RING1B with chromosomal DNA was cell cycle dependent in human osteosarcoma cells, and expression was strongest in interphase centromeric regions.
Wang et al. (2004) showed that an E3 ubiquitin ligase complex, which they designated Polycomb repressive complex-1-like (PRC1L), specifically monoubiquitinates histone-2A (H2A; see 142711) at lys119. They found that PRC1L is composed of several PcG proteins, including RING1, RNF2, BMI1, and HPH2 (EDR2). Reduction of RNF2 expression resulted in a dramatic decrease in the level of ubiquitinated H2A in HeLa cells. Wang et al. (2004) proposed that H2A ubiquitination is linked to Polycomb silencing.
De Napoles et al. (2004) found that the PRC1 proteins Mel18 and Ring1B were transiently enriched on inactive X chromosomes (Xi) during early mouse development. Xi was also highly enriched in ubiquitylated H2A (uH2A), and this occurred coincident with PRC1 recruitment. Analysis of cells lacking Ring1b and Ring1a proteins demonstrated that Ring1b is required to maintain global uH2A levels in embryonic stem cells and that Ring1a and Ring1b have an overlapping function in maintaining uH2A on Xi in differentiated cells.
To gain insight into the role of PcG proteins in embryonic stem (ES) cells, Boyer et al. (2006) identified the genes occupied by PcG proteins in murine ES cells by performing genomewide location analysis using antibodies against core components of PRC1 (Phc1, 602978 and Rnf2) and PRC2 (Suz12, 606245 and Eed, 605984). Boyer et al. (2006) found that the Polycomb repressive complexes PRC1 and PRC2 co-occupied 512 genes, many of which encode transcription factors with important roles in development. All of the co-occupied genes contained modified nucleosomes (trimethylated lys27 on histone H3; see 602810). Consistent with a causal role in gene silencing in ES cells, PcG target genes were derepressed in cells deficient for the PRC2 component Eed, and were preferentially activated on induction of differentiation. Boyer et al. (2006) concluded that dynamic repression of developmental pathways by Polycomb complexes may be required for maintaining ES cell pluripotency and plasticity during embryonic development.
Terranova et al. (2008) found that mouse Ezh2 (601573) and Rnf2 were independently required for genomic contraction and repression of imprinted genes during early embryonic development.
Yokobayashi et al. (2013) identified gene dosage-dependent roles in primordial germ cell (PGC) development for Ring1 and Rnf2, 2 central components of PRC1. Both paralogs are essential for PGC development between days 10.5 and 11.5 of gestation. Rnf2 is subsequently required in female PGCs to maintain high levels of Oct4 (164177) and Nanog (607937) expression and to prevent premature induction of meiotic gene expression and entry into meiotic prophase. Chemical inhibition of retinoic acid signaling partially suppresses precocious Oct4 downregulation and Stra8 (609987) activation in Rnf2-deficient female PGCs. Chromatin immunoprecipitation analyses showed that Stra8 is a direct target of PRC1 and PRC2 in PGcs. Yokobayashi et al. (2013) concluded that their data demonstrated the importance of PRC1 gene dosage in PGC development and in coordinating the timing of sex differentiation of female PGCs by antagonizing extrinsic retinoic acid signaling.
Crystal Structure
McGinty et al. (2014) crystallized the Polycomb repressive complex-1 (PRC1) ubiquitylation module, an E2-E3 enzyme complex composed of UBCH5C (602963) and the minimal RING1B-BMI1 (164831) ring heterodimer, bound to its nucleosome core particle substrate. The authors solved the structure at 3.3-angstrom resolution. The structure shows how a chromatin enzyme achieves substrate specificity by interacting with several nucleosome surfaces spatially distinct from the site of catalysis. McGinty et al. (2014) concluded that the structure revealed an unexpected role for the ubiquitin E2 enzyme in substrate recognition, and provides insight into how a related histone H2A E3 ligase, BRCA1 (113705), interacts with and ubiquitylates the nucleosome.
In 2 unrelated girls with Luo-Schoch-Yamamoto syndrome (LUSYAM; 619460), Luo et al. (2021) identified de novo heterozygous missense mutations in the RNF2 gene (R70H; 608985.0001 and S82R; 608985.0002). Both mutations occurred at conserved residues in the zinc finger motif. The mutations, which were found by genome or exome sequencing, were not present in the gnomAD database. Functional studies of patient cells were not performed, but neither mutation was able to rescue lethality in a Drosophila model with knockdown of the orthologous gene (Sce). Further studies in Drosophila indicated that R70H is an amorphic allele, whereas S82R is hypomorphic, consistent with a loss-of-function effect and haploinsufficiency.
Suzuki et al. (2002) created mice with reduced Ring1b expression due to homozygosity for a hypomorphic Ring1b allele, which they termed Ring1b(red). Ring1b(red) homozygotes were healthy and fertile, but they had axial skeletal abnormalities and depressed expression of some Hox genes, such as Hoxb4 (142965), in cells anterior to their normal boundaries of expression in the mesodermal compartment. In contrast, overexpression of Ring1b in chick embryos resulted in repression of Hoxb9 (142964) expression in the neural tube. Suzuki et al. (2002) concluded that RING1B is involved in the regulation of HOX gene expression by PcG complexes.
Voncken et al. (2003) generated mice lacking Rnf2, which resulted in gastrulation arrest similar to that seen in Eed (605984) -/- mice and Ezh2 -/- mice. A partial bypass of the early embryonic arrest could be achieved by inactivation of the Cdkn2a (600160) tumor suppressor locus. Voncken et al. (2003) concluded that both group I and group II Polycomb repressors are essential during early mammalian development.
In an 11-year-old girl (patient 1) with Luo-Schoch-Yamamoto syndrome (LUSYAM; 619460), Luo et al. (2021) identified a de novo heterozygous c.209G-A transition (c.209G-A, NM_007212.3) in the RNF2 gene, resulting in an arg70-to-his (R70H) substitution at a conserved residue in the zinc finger motif. The mutation, which was found by genome sequencing, was not present in the gnomAD database. Functional studies of patient cells were not performed, but the mutation was unable to rescue lethality in a Drosophila model with knockdown of the orthologous gene (Sce), consistent with a loss of function and haploinsufficiency. Further studies indicated that it is an amorphic allele.
In a 3.5-year-old girl (patient 2) with Luo-Schoch-Yamamoto syndrome (LUSYAM; 619460), Luo et al. (2021) identified a de novo heterozygous c.246T-G transversion (c.246T-G, NM_007212.3) in the RNF2 gene, resulting in a ser82-to-arg (S82R) substitution at a conserved residue in the zinc finger motif. The mutation, which was found by exome sequencing, was not present in the gnomAD database. Functional studies of patient cells were not performed, but the mutation was unable to rescue lethality in a Drosophila model with knockdown of the orthologous gene (Sce), consistent with a loss of function and haploinsufficiency. Further studies in Drosophila indicated that it is a hypomorphic allele.
Boyer, L. A., Plath, K., Zeitlinger, J., Brambrink, T., Medeiros, L. A., Lee, T. I., Levine, S. S., Wernig, M., Tajonar, A., Ray, M. K., Bell, G. W., Otte, A. P., Vidal, M., Gifford, D. K., Young, R. A., Jaenisch, R. Polycomb complexes repress developmental regulators in murine embryonic stem cells. Nature 441: 349-353, 2006. [PubMed: 16625203] [Full Text: https://doi.org/10.1038/nature04733]
de Napoles, M., Mermoud, J. E., Wakao, R., Tang, Y. A., Endoh, M., Appanah, R., Nesterova, T. B., Silva, J., Otte, A. P., Vidal, M., Koseki, H., Brockdorff, N. Polycomb group proteins Ring1A/B link ubiquitylation of histone H2A to heritable gene silencing and X inactivation. Dev. Cell 7: 663-676, 2004. [PubMed: 15525528] [Full Text: https://doi.org/10.1016/j.devcel.2004.10.005]
Gross, M. B. Personal Communication. Baltimore, Md. 8/4/2021.
Lee, S.-J., Choi, J.-Y., Sung, Y.-M., Park, H., Rhim, H., Kang, S. E3 ligase activity of RING finger proteins that interact with Hip-2, a human ubiquitin-conjugating enzyme. FEBS Lett. 503: 61-64, 2001. [PubMed: 11513855] [Full Text: https://doi.org/10.1016/s0014-5793(01)02689-8]
Luo, X., Schoch, K., Jangam, S. V., Bhavana, V. H., Graves, H. K., Kansagra, S., Jasien, J. M., Strong, N., Keren, B., Mignot, C., Ravelli, C., Undiagnosed Diseases Network, Bellen, H. J., Wangler, M. F., Shashi, V., Yamamoto, S. Rare deleterious de novo missense variants in Rnf2/Ring2 are associated with a neurodevelopmental disorder with unique clinical features. Hum. Molec. Genet. 30: 1283-1292, 2021. [PubMed: 33864376] [Full Text: https://doi.org/10.1093/hmg/ddab110]
McGinty, R. K., Henrici, R. C., Tan, S. Crystal structure of the PRC1 ubiquitylation module bound to the nucleosome. Nature 514: 591-596, 2014. [PubMed: 25355358] [Full Text: https://doi.org/10.1038/nature13890]
Suzuki, M., Mizutani-Koseki, Y., Fujimura, Y., Miyagishima, H., Kaneko, T., Takada, Y., Akasaka, T., Tanzawa, H., Takihara, Y., Nakano, M., Masumoto, H., Vidal, M., Isono, K., Koseki, H. Involvement of the Polycomb-group gene Ring1B in the specification of the anterior-posterior axis in mice. Development 129: 4171-4183, 2002. [PubMed: 12183370] [Full Text: https://doi.org/10.1242/dev.129.18.4171]
Terranova,, R., Yokobayashi, S., Stadler, M. B., Otte, A. P., van Lohuizen, M., Orkin, S. H., Peters, A. H. F. M. Polycomb group proteins Ezh2 and Rnf2 direct genomic contraction and imprinted repression in early mouse embryos. Dev. Cell 15: 668-679, 2008. [PubMed: 18848501] [Full Text: https://doi.org/10.1016/j.devcel.2008.08.015]
Tuckfield, A., Clouston, D. R., Wilanowski, T. M., Zhao, L.-L., Cunningham, J. M., Jane, S. M. Binding of the RING Polycomb proteins to specific target genes in complex with the grainyhead-like family of developmental transcription factors. Molec. Cell. Biol. 22: 1936-1946, 2002. [PubMed: 11865070] [Full Text: https://doi.org/10.1128/MCB.22.6.1936-1946.2002]
Voncken, J. W., Roelen, B. A. J., Roefs, M., de Vries, S., Verhoeven, E., Marino, S., Deschamps, J., van Lohuizen, M. Rnf2 (Ring1b) deficiency causes gastrulation arrest and cell cycle inhibition. Proc. Nat. Acad. Sci. 100: 2468-2473, 2003. [PubMed: 12589020] [Full Text: https://doi.org/10.1073/pnas.0434312100]
Wang, H., Wang, L., Erdjument-Bromage, H., Vidal, M., Tempst, P., Jones, R. S., Zhang, Y. Role of histone H2A ubiquitination in Polycomb silencing. Nature 431: 873-878, 2004. [PubMed: 15386022] [Full Text: https://doi.org/10.1038/nature02985]
Yokobayashi, S., Liang, C.-Y., Kohler, H., Nestorov, P., Liu, Z., Vidal M., van Lohuizen, M., Roloff, T. C., Peters, A. H. F. M. PRC1 coordinates timing of sexual differentiation of female primordial germ cells. Nature 495: 236-240, 2013. [PubMed: 23486062] [Full Text: https://doi.org/10.1038/nature11918]