| Structural highlights
Function
[RMI1_HUMAN] Essential component of the RMI complex, a complex that plays an important role in the processing of homologous recombination intermediates to limit DNA crossover formation in cells. Promotes TOP3A binding to double Holliday junctions (DHJ) and hence stimulates TOP3A-mediated dissolution. Required for BLM phosphorylation during mitosis. Within the BLM complex, required for BLM and TOP3A stability.[1] [2] [3] [RMI2_HUMAN] Essential component of the RMI complex, a complex that plays an important role in the processing of homologous recombination intermediates to limit DNA crossover formation in cells. The complex is therefore essential for the stability, localization, and function of complexes containing BLM. In the RMI complex, it is required to target BLM to chromatin and stress-induced nuclear foci and mitotic phosphorylation of BLM.[4] [5]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Mutations in BLM, a RecQ-like helicase, are linked to the autosomal recessive cancer-prone disorder Bloom's syndrome. BLM associates with topoisomerase (Topo) IIIalpha, RMI1, and RMI2 to form the BLM complex that is essential for genome stability. The RMI1-RMI2 heterodimer stimulates the dissolution of double Holliday junction into non-crossover recombinants mediated by BLM-Topo IIIalpha and is essential for stabilizing the BLM complex. However, the molecular basis of these functions of RMI1 and RMI2 remains unclear. Here we report the crystal structures of multiple domains of RMI1-RMI2, providing direct confirmation of the existence of three oligonucleotide/oligosaccharide binding (OB)-folds in RMI1-RMI2. Our structural and biochemical analyses revealed an unexpected insertion motif in RMI1N-OB, which is important for stimulating the dHJ dissolution. We also revealed the structural basis of the interaction between RMI1C-OB and RMI2-OB and demonstrated the functional importance of the RMI1-RMI2 interaction in genome stability maintenance.
Crystal structures of RMI1 and RMI2, two OB-fold regulatory subunits of the BLM complex.,Wang F, Yang Y, Singh TR, Busygina V, Guo R, Wan K, Wang W, Sung P, Meetei AR, Lei M Structure. 2010 Sep 8;18(9):1159-70. PMID:20826342[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Yin J, Sobeck A, Xu C, Meetei AR, Hoatlin M, Li L, Wang W. BLAP75, an essential component of Bloom's syndrome protein complexes that maintain genome integrity. EMBO J. 2005 Apr 6;24(7):1465-76. Epub 2005 Mar 17. PMID:15775963 doi:http://dx.doi.org/7600622
- ↑ Raynard S, Bussen W, Sung P. A double Holliday junction dissolvasome comprising BLM, topoisomerase IIIalpha, and BLAP75. J Biol Chem. 2006 May 19;281(20):13861-4. Epub 2006 Apr 4. PMID:16595695 doi:http://dx.doi.org/C600051200
- ↑ Wu L, Bachrati CZ, Ou J, Xu C, Yin J, Chang M, Wang W, Li L, Brown GW, Hickson ID. BLAP75/RMI1 promotes the BLM-dependent dissolution of homologous recombination intermediates. Proc Natl Acad Sci U S A. 2006 Mar 14;103(11):4068-73. Epub 2006 Mar 6. PMID:16537486 doi:http://dx.doi.org/10.1073/pnas.0508295103
- ↑ Xu D, Guo R, Sobeck A, Bachrati CZ, Yang J, Enomoto T, Brown GW, Hoatlin ME, Hickson ID, Wang W. RMI, a new OB-fold complex essential for Bloom syndrome protein to maintain genome stability. Genes Dev. 2008 Oct 15;22(20):2843-55. PMID:18923082 doi:http://dx.doi.org/22/20/2843
- ↑ Singh TR, Ali AM, Busygina V, Raynard S, Fan Q, Du CH, Andreassen PR, Sung P, Meetei AR. BLAP18/RMI2, a novel OB-fold-containing protein, is an essential component of the Bloom helicase-double Holliday junction dissolvasome. Genes Dev. 2008 Oct 15;22(20):2856-68. PMID:18923083 doi:http://dx.doi.org/22/20/2856
- ↑ Wang F, Yang Y, Singh TR, Busygina V, Guo R, Wan K, Wang W, Sung P, Meetei AR, Lei M. Crystal structures of RMI1 and RMI2, two OB-fold regulatory subunits of the BLM complex. Structure. 2010 Sep 8;18(9):1159-70. PMID:20826342 doi:10.1016/j.str.2010.06.008
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