| Structural highlights
Function
SPOVM_BACSU Coordinates cortex and coat assembly during sporulation (PubMed:22463703, PubMed:8231808). Associates with the spore coat protein SpoIVA and with the outer forespore membrane, thereby serving as a membrane anchor that tethers SpoIVA and the entire spore coat to the forespore surface (PubMed:17427285). May also serve as a competitive inhibitor of FtsH activity during sporulation (PubMed:9287010).[1] [2] [3] [4]
Publication Abstract from PubMed
In bacteria, certain shape-sensing proteins localize to differently curved membranes. During sporulation in Bacillus subtilis, the only convex (positively curved) surface in the cell is the forespore, an approximately spherical internal organelle. Previously, we demonstrated that SpoVM localizes to the forespore by preferentially adsorbing onto slightly convex membranes. Here, we used NMR and molecular dynamics simulations of SpoVM and a localization mutant (SpoVMP9A) to reveal that SpoVM's atypical amphipathic alpha-helix inserts deeply into the membrane and interacts extensively with acyl chains to sense packing differences in differently curved membranes. Based on binding to spherical supported lipid bilayers and Monte Carlo simulations, we hypothesize that SpoVM's membrane insertion, along with potential cooperative interactions with other SpoVM molecules in the lipid bilayer, drives its preferential localization onto slightly convex membranes. Such a mechanism, which is distinct from that used by high curvature-sensing proteins, may be widely conserved for the localization of proteins onto the surface of cellular organelles.
Structural basis for the geometry-driven localization of a small protein.,Gill RL Jr, Castaing JP, Hsin J, Tan IS, Wang X, Huang KC, Tian F, Ramamurthi KS Proc Natl Acad Sci U S A. 2015 Mar 30. pii: 201423868. PMID:25825747[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ramamurthi KS, Clapham KR, Losick R. Peptide anchoring spore coat assembly to the outer forespore membrane in Bacillus subtilis. Mol Microbiol. 2006 Dec;62(6):1547-57. PMID:17427285 doi:10.1111/j.1365-2958.2006.05468.x
- ↑ Ebmeier SE, Tan IS, Clapham KR, Ramamurthi KS. Small proteins link coat and cortex assembly during sporulation in Bacillus subtilis. Mol Microbiol. 2012 May;84(4):682-96. PMID:22463703 doi:10.1111/j.1365-2958.2012.08052.x
- ↑ Levin PA, Fan N, Ricca E, Driks A, Losick R, Cutting S. An unusually small gene required for sporulation by Bacillus subtilis. Mol Microbiol. 1993 Aug;9(4):761-71. PMID:8231808 doi:10.1111/j.1365-2958.1993.tb01736.x
- ↑ Cutting S, Anderson M, Lysenko E, Page A, Tomoyasu T, Tatematsu K, Tatsuta T, Kroos L, Ogura T. SpoVM, a small protein essential to development in Bacillus subtilis, interacts with the ATP-dependent protease FtsH. J Bacteriol. 1997 Sep;179(17):5534-42. PMID:9287010 doi:10.1128/jb.179.17.5534-5542.1997
- ↑ Gill RL Jr, Castaing JP, Hsin J, Tan IS, Wang X, Huang KC, Tian F, Ramamurthi KS. Structural basis for the geometry-driven localization of a small protein. Proc Natl Acad Sci U S A. 2015 Mar 30. pii: 201423868. PMID:25825747 doi:http://dx.doi.org/10.1073/pnas.1423868112
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