Crystal Structures of RMI1 and RMI2, Two OB-Fold Regulatory Subunits of the BLM Complex

Journal Article · Fri Nov 05 00:00:00 EDT 2010 · Structure

DOI:https://doi.org/10.1016/j.str.2010.06.008· OSTI ID:1002750

Wang, Feng; Yang, Yuting; Singh, Thiyam Ramsing; Busygina, Valeria; Guo, Rong; Wan, Ke; Wang, Weidong; Sung, Patrick; Meetei, Amom Ruhikanta; Lei, Ming ^[1]

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1. Yale-MED

Mutations in BLM, a RecQ-like helicase, are linked to the autosomal recessive cancer-prone disorder Bloom's syndrome. BLM associates with topoisomerase (Topo) III{alpha}, 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 III{alpha} 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.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
• Sponsoring Organization: USDOE
• OSTI ID: 1002750
• Journal Information: Structure, Vol. 18, Issue (9) ; 09, 2010
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL STRUCTURE
DISSOLUTION
FUNCTIONALS
MAINTENANCE
MUTATIONS
STABILITY