| TCID | Name | Domain | Kingdom/Phylum | Protein(s) |
|---|---|---|---|---|
|
9.A.57.1.1 | Extended synaptotagmin T1, EsyT1, of 1104 aas and 2 TMSs. The protein has two C2 domains, C2A and C2B, which interact with numberous proteins individually or together. These include those involved in synaptic transmission, metabolic regulation and transport (Guo et al. 2017). It binds glycerophospholipids in a barrel-like domain and may play a role in cellular lipid transport. It also binds calcium (via the C2 domains) and translocates to sites of contact between the endoplasmic reticulum (ER) and the cell membrane in response to increased cytosolic calcium levels (Chang et al. 2013). It helps tether the ER to the cell membrane and promotes the formation of appositions between the ER and the cell membrane. See family description for more details and references. ESYT1 tethers the ER to mitochondria via mitochondria-ER contact sites (MERCs), and is required for mitochondrial lipid and calcium homeostasis (Janer et al. 2024). Thus, ESYT1 plays a role in mitochondrial and cellular homeostasis through its role in the regulation of MERCs. | Eukaryota |
Metazoa, Chordata | EsyT1 of Homo sapiens |
|
9.A.57.1.2 | Extended synaptotagmin T2, EsyT2, of 921 aas and 2 TMSs. See family description for details and references. | Bacteria |
Metazoa, Chordata | EsyT2 of Homo sapiens |
|
9.A.57.1.3 | Extended synaptotagmin T3, EsyT3, of 886 aas and 2 TMSs. See family description for details and references. Contains three C2 Ca2+-binding domains of unknown function but found in many signal transduction proteins. Extended synaptotagmins are Ca2+-dependent lipid transfer proteins found at membrane contact sites. (Yu et al. 2016). | Eukaryota |
Metazoa, Chordata | EsyT3 of Homo sapiens |
|
9.A.57.1.4 | Extended synaptotagmin-like protein T2, EsyL2, of 934 aas and 2 TMSs. See family description for details and references. | Eukaryota |
Metazoa, Chordata | EsyL2 of Homo sapiens |
|
9.A.57.1.5 | The FT-INTERACTING PROTEIN 1 (FTIP1) is a member of the family of multiple C2 domain and transmembrane region proteins (MCTPs). In rice, it is required for the export of RICE FLOWERING LOCUS T 1 (RFT1) (Song et al. 2017). It is 68% identical to FTIP3 which is involved in trafficking that regulates shoot meristem development (Liu et al. 2018). FTIP3/4 prevent intracellular trafficking of a key regulator, SHOOTMERISTEMLESS (STM), to the plasma membrane in cells in the peripheral shoot meristem region (Liu et al. 2018). | Eukaryota |
Viridiplantae, Streptophyta | FTIP1 of Arabidopsis thaliana (Mouse-ear cress) |
|
9.A.57.1.6 | The Multiple C2 and transmembrane domain-containing protein 2, MCTP2, of 878 aas. It probably functions in peroxisome biogenesis (see TC# 3.A.20) and lipid droplet formation in higher eukaryotes. It is probably analogous to the Pex30 protein in yeast (Joshi et al. 2018). | Eukaryota |
Metazoa, Chordata | MCTP2 of Homo sapiens |
|
9.A.57.1.7 | Quirky, Qky, of 1081aas and two C-terminal TMSs. Interacts with Syntaxin-121 (TC# 8.A.91.1.7) which regulates K+ channels such as KAT3 (TC# 1.A.1.4.9; Honsbein et al. 2009). May also be involved in Ca2+-dependent signaling and membrane trafficking. | Eukaryota |
Viridiplantae, Streptophyta | Quirky of Arabidopsis thaliana (Mouse-ear cress) |
|
9.A.57.1.8 | Synaptotagmin-like protein 4, SYTL4, of 671 aas. It modulates exocytosis of dense-core granules and
secretion of hormones in the pancreas and the pituitary. It also interacts with
vesicles containing negatively charged phospholipids in a Ca2+-independent manner (Izumi et al. 2007). Mutations give rise to high functioning autism (Rafi et al. 2019). | Eukaryota |
Metazoa, Chordata | SYLT4 of Homo sapiens |
|
9.A.57.1.9 | Putative synaptotagmin homolog of 1258 aas and from 1 to 6 TMSs. This protein is annotated as a metal ion transporter, metal ion (Mn2+/Fe2+) transporter (Nramp) family protein, but it does not appear to be related to this family. | Eukaryota |
Fungi, Ascomycota | Synaptotagmin homolog of Aspergillus niger |
|
9.A.57.1.10 | Yeast tricalbin 1 of 1186 aas and 1 or 2 N-terminal TMSs and possibly one more at the C-erminus of the protein. It binds 3 Ca2+ ions per subunit, which are bound to the C2 domains. There are three types of tricalbins (1, 2 and 3) in S. cerevisiae (see TC#s 9.A.57.1.10, 11, and 12). | Eukaryota |
Fungi, Ascomycota | Tricalbin 1 of Saccharomyces cerevisiae |
|
9.A.57.1.11 | Tricalbin 2 of 1178 aas and 1, 2 or 3 TMSs, one or two at the N-erminus and possibly one more at the C-terminus. | Eukaryota |
Fungi, Ascomycota | Tricalbin 2 of Saccharomycel cerevisiae |
|
9.A.57.1.12 | Smith et al. 2024 showed that ER-plasma membrane contact sites deliver ER lipids and proteins for rapid cell surface expansion. Tricalbin 3 of 1545 aas and possibly 1 or 2 TMSs, near the N-terminus of the protein may be involved. ER-plasma membrane contact sites deliver ER lipids and proteins for rapid cell surface expansion (Smith et al. 2024). As a consequence of hypoosmotic shock, yeast cells swell rapidly and increase their surface area by ∼20% in 20 s. Approximately, 35% of this surface increase is mediated by the ER-plasma membrane contact sites, specifically the tricalbins, which are required for the delivery of both lipids and the GPI-anchored protein Crh2 from the cortical ER to the plasma membrane. Therefore, Smith et al. 2024 proposed a new function for the tricalbins: mediating the fusion of the ER to the plasma membrane at contact sites. This proposed fusion is triggered by calcium influx via the stretch-gated channel Cch1 (TC# 1.A.1.11.10) and is supported by the anoctamin Ist2 (TC# 1.A.17.1.19). | Eukaryota |
Fungi, Ascomycota | Tricalbin 3 of 1545 aas and 2 possible TMSs, N- and C-terminally from Saccharomyces cerevisiae. |