1.A.14.2.3 The 7 TMS proton-sensitive Ca2+ leak channel, YetJ. The activity and high resolution 3-d structure have been determined (Chang et al. 2014). BsYetJ in lipid nanodiscs is structurally different from those crystallized in detergents. Li et al. 2020 showed that the BsYetJ conformation is pH-sensitive in the apo state (lacking calcium), whereas in a calcium-containing solution it is stuck in an intermediate state, inert to pH changes. Only when the transmembrane calcium gradient is established can the calcium-release activity of holo-BsYetJ occur and be mediated by pH-dependent conformational changes, suggesting a dual gating mechanism. Conformational substates involved in the process and a key residue, D171, relevant to the gating of calcium were identified. Thus, BsYetJ/TMBIM6 is a pH-dependent, voltage-gated calcium channel (Li et al. 2020).
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Accession Number: | O31539 |
Protein Name: | Uncharacterized protein YetJ |
Length: | 214 |
Molecular Weight: | 23829.00 |
Species: | Bacillus subtilis [1423] |
Number of TMSs: | 7 |
Location1 / Topology2 / Orientation3: |
Cell membrane1 / Multi-pass membrane protein2 |
Substrate |
calcium(2+) |
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1: MQATVHESKQ SIMQRILTVF VFTLLIATVG LFIGQFVPVA LMLPLSILEV AMIILAFWMR
61: RRKAVGYAFV YTFAFVSGIT LFPIVSHYAS IAGAYVVLEA FGSTFVIFAV LGTIGAKMKK
121: DLSFLWSFLL VAVLALAVVG IFNIFSPLNS AAMMAYSVIG TIVFSLYILY DLNQIKHRHI
181: TEDLIPVMAL SLYLDFINLF INLLRFFGIL SSDD