Structural highlights
Function
MD2L1_HUMAN Component of the spindle-assembly checkpoint that prevents the onset of anaphase until all chromosomes are properly aligned at the metaphase plate. Required for the execution of the mitotic checkpoint which monitors the process of kinetochore-spindle attachment and inhibits the activity of the anaphase promoting complex by sequestering CDC20 until all chromosomes are aligned at the metaphase plate.[1] [2] [3]
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
The 25 kDa Mad2 protein is a key player in the spindle assembly checkpoint, a safeguard against chromosome segregation errors in mitosis. Mad2 combines three unusual properties. First, Mad2 adopts two conformations with distinct topologies, open (O) and closed (C) Mad2. Second, C-Mad2 forms topological links with its two best-characterized protein ligands, Mad1 and Cdc20. Third, O-Mad2 and C-Mad2 engage in a "conformational" dimer that is essential for spindle checkpoint function in different organisms. The crystal structure of the O-Mad2-C-Mad2 conformational dimer, reported here, reveals an asymmetric interface that explains the selective dimerization of the O-Mad2 and C-Mad2 conformers. The structure also identifies several buried hydrophobic residues whose rearrangement correlates with the Mad2 topological change. The structure of the O-Mad2-C-Mad2 conformational dimer is consistent with a catalytic model in which a C-Mad2 template facilitates the binding of O-Mad2 to Cdc20, the target of Mad2 in the spindle checkpoint.
The Mad2 conformational dimer: structure and implications for the spindle assembly checkpoint.,Mapelli M, Massimiliano L, Santaguida S, Musacchio A Cell. 2007 Nov 16;131(4):730-43. PMID:18022367[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Luo X, Fang G, Coldiron M, Lin Y, Yu H, Kirschner MW, Wagner G. Structure of the Mad2 spindle assembly checkpoint protein and its interaction with Cdc20. Nat Struct Biol. 2000 Mar;7(3):224-9. PMID:10700282 doi:10.1038/73338
- ↑ Luo X, Tang Z, Rizo J, Yu H. The Mad2 spindle checkpoint protein undergoes similar major conformational changes upon binding to either Mad1 or Cdc20. Mol Cell. 2002 Jan;9(1):59-71. PMID:11804586
- ↑ Luo X, Tang Z, Xia G, Wassmann K, Matsumoto T, Rizo J, Yu H. The Mad2 spindle checkpoint protein has two distinct natively folded states. Nat Struct Mol Biol. 2004 Apr;11(4):338-45. Epub 2004 Mar 14. PMID:15024386 doi:10.1038/nsmb748
- ↑ Mapelli M, Massimiliano L, Santaguida S, Musacchio A. The Mad2 conformational dimer: structure and implications for the spindle assembly checkpoint. Cell. 2007 Nov 16;131(4):730-43. PMID:18022367 doi:10.1016/j.cell.2007.08.049
