| TCID | Name | Domain | Kingdom/Phylum | Protein(s) |
|---|---|---|---|---|
|
9.A.78.1.1 | Membrane-associated phosphatidylinositol transfer protein 1, PITPNM1, of 1244 aas and possibly 8 TMSs in a 4 + 4 TMS arrangement. It catalyzes the transfer of phosphatidylinositol (PI) between membranes (Garner et al. 2012, Fullwood et al. 1999). It binds PI, phosphatidylcholine (PC) and phosphatidic acid (PA) with the binding affinity order of PI > PA > PC (Garner et al. 2012) and regulates RHOA activity while playing a role in cytoskeleton remodeling (Tian et al. 2002). It is necessary for normal completion of cytokinesis (Litvak et al. 2004) and plays a role in maintaining normal diacylglycerol levels in the Golgi apparatus (Litvak et al. 2005). It seems to be necessary for maintaining the normal structure of the endoplasmic reticulum and the Golgi apparatus (Amarilio et al. 2005) and is required for protein export from the endoplasmic reticulum and the Golgi (Litvak et al. 2005). It binds calcium ions (Lev et al. 1999). | Eukaryota |
Metazoa, Chordata | PITPNM1 of Homo sapiens |
|
9.A.78.1.2 | Protein retinal degeneration B, RdgB, of 1259 aas, possibly with a central 8 TMSs unit in a 4 + 4 TMS arrangement. It catalyzes the transfer of phosphatidylinositol (PI) and phosphatidic acid (PA) between membranes (Garner et al. 2012). It may control the phosphatidylinositol concentration in transport vesicles from the subrhabdomeric cisternae (SRC) to the rhabdomere as well as functioning as a calcium transporter (Vihtelic et al. 1991). Lipid transfer proteins mediate the transfer of lipids between organelle membranes, and the loss of function of these proteins has been linked to neurodegeneration. In Drosophila photoreceptors, depletion of retinal degeneration B (RDGB), a phosphatidylinositol transfer protein, leads to defective phototransduction and retinal degeneration. RDGB is localized to membrane contact sites through the interaction of its FFAT motif with the ER integral protein VAP. To identify regulators of RDGB function in vivo, Mishra et al. 2024 depleted more than 300 VAP-interacting proteins and identified a set of 52 suppressors of rdgB. The molecular identity of these suppressors indicates a role of novel lipids in regulating RDGB function and of transcriptional and ubiquitination processes in mediating retinal degeneration in rdgB. The human homologs of several of these molecules have been implicated in neurodevelopmental diseases, underscoring the importance of VAP-mediated processes in these disorders. | Eukaryota |
Metazoa, Arthropoda | RdgB of Drosophila melanogaster (Fruit fly) |
|
9.A.78.1.3 | Phospholipase DDHD1 isoform X3 of 621 aas and possibly 4 C-terminal TMSs. | Eukaryota |
Metazoa, Chordata | DDHD1 of Leptonychotes weddellii |
|
9.A.78.1.4 | Phospholipase DDHD2 isoform X5 of 732 aas and ? TMSs. | Eukaryota |
Metazoa, Chordata | DDHD2.5 of Oryzias melastigma |
|
9.A.78.1.5 | Putative phosphatase of 995 aas and possibly 4 central TMSs. | Eukaryota |
Fungi, Ascomycota | Phosphatase of Colletotrichum viniferum |
|
9.A.78.1.6 | DDHD-domain-containing protein of 677 aas and possibly 4 central TMSs. | Eukaryota |
Sar | Possible phosphatase of Fragilariopsis cylindrus |
|
9.A.78.1.7 | Phosphatidylinositol transfer protein, PITP, of 271 aas (Hsu et al. 2025).
| None |
Metazoa, Chordata | PITP of Homo sapiens |