Structural highlights
Function
[MSS4_HUMAN] Guanine-nucleotide-releasing protein that acts on members of the SEC4/YPT1/RAB subfamily. Stimulates GDP release from both YPT1 and RAB3A, but is less active on these proteins than on the SEC4 protein. Might play a general role in vesicular transport.
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
Guanine-nucleotide-exchange factors (GEFs) promote the exchange of GDP for GTP in Ras GTPases, and thereby positively regulate their functions. Members of the Sec4/Ypt1/Rab branch of the Ras superfamily are essential for vesicular transport. A GEF for a subset of Rab proteins, termed mammalian suppressor of Sec4 (Mss4), has been identified. Here we use multidimensional NMR to determine the structure of human Mss4 (hMss4), which is the first tertiary structure established for a protein with GEF activity. Mss4 contains a central beta-sheet sandwiched between two small sheets. It also binds a Zn2+ ion through Cys 23, Cys 26, Cys 94 and Cys 97. The Rab-binding surface of hMss4 has subsequently been delineated using chemical-shift perturbation experiments and site-directed mutagenesis. The active site of hMss4 involves the Zn(2+)-binding region and a neighbouring loop.
Structure of guanine-nucleotide-exchange factor human Mss4 and identification of its Rab-interacting surface.,Yu H, Schreiber SL Nature. 1995 Aug 31;376(6543):788-91. PMID:7651540[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Yu H, Schreiber SL. Structure of guanine-nucleotide-exchange factor human Mss4 and identification of its Rab-interacting surface. Nature. 1995 Aug 31;376(6543):788-91. PMID:7651540 doi:http://dx.doi.org/10.1038/376788a0