Pathways & interactions
Mechanosensitive ion channel MscS (IPR006685)
Short name: MscS_channel
Overlapping homologous superfamilies
- LSM domain superfamily (IPR010920)
- Mechanosensitive ion channel MscS domain superfamily (IPR023408)
- Mechanosensitive ion channel MscS (IPR006685)
- Mechanosensitive ion channel MscS-like, plants/fungi (IPR016688)
- Miniconductance mechanosensitive channel YbdG (IPR030192)
- Predicted ion channel, cNMP-binding (IPR016846)
This entry represents a family of small conductance mechanosensitive channels (MscS).
Mechanosensitive (MS) channels provide protection against hypo-osmotic shock, responding both to stretching of the cell membrane and to membrane depolarisation. They are present in the membranes of organisms from the three domains of life: bacteria, archaea, and eukarya [PMID: 12626684]. There are two families of MS channels: large-conductance MS channels (MscL) and small-conductance MS channels (MscS or YGGB). The pressure threshold for MscS opening is 50% that of MscL [PMID: 12446901]. The MscS family is much larger and more variable in size and sequence than the MscL family. Much of the diversity in MscS proteins occurs in the size of the transmembrane regions, which ranges from three to eleven transmembrane helices, although the three C-terminal helices are conserved.
MscS folds as a homo-heptamer with a cylindrical shape, and can be divided into transmembrane and extramembrane regions: an N-terminal periplasmic region, a transmembrane region, and a C-terminal cytoplasmic region (middle and C-terminal domains). The transmembrane region forms a channel through the membrane that opens into a chamber enclosed by the extramembrane portion, the latter connecting to the cytoplasm through distinct portals [PMID: 12446901].
- PF00924 (MS_channel)