UniProt functional annotation for Q9UNF0

UniProt code: Q9UNF0.

Organism: Homo sapiens (Human).
Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.
 
Function: Regulates the morphogenesis and endocytosis of caveolae (By similarity). Lipid-binding protein that is able to promote the tubulation of the phosphatidic acid-containing membranes it preferentially binds. Plays a role in intracellular vesicle-mediated transport. Involved in the endocytosis of cell-surface receptors like the EGF receptor, contributing to its internalization in the absence of EGF stimulus. {ECO:0000250|UniProtKB:Q9WVE8, ECO:0000269|PubMed:21693584, ECO:0000269|PubMed:23129763, ECO:0000269|PubMed:23236520, ECO:0000269|PubMed:23596323}.
 
Function: (Microbial infection) Specifically enhances the efficiency of HIV-1 virion spread by cell-to-cell transfer (PubMed:29891700). Also promotes the protrusion engulfment during cell-to-cell spread of bacterial pathogens like Listeria monocytogenes (PubMed:31242077). Involved in lipid droplet formation, which is important for HCV virion assembly (PubMed:31801866). {ECO:0000269|PubMed:29891700, ECO:0000269|PubMed:31242077, ECO:0000269|PubMed:31801866}.
 
Subunit: Homodimer (By similarity). May form heterooligomers with other PACSINs (By similarity). Interacts (via NPF motifs) with EHD1 (via EH domain) (PubMed:23596323). Interacts (via NPF motifs) with EHD2 (via EH domain); this interaction probably stabilizes the caveolae (PubMed:22323287). Interacts with EHD3 (PubMed:23596323). Interacts (via the SH3 domain) with MICALL1 (PubMed:23596323). Interacts with RAC1 (PubMed:21693584). Interacts (via SH3 domain) with DNM1, SYN1, SYNJ1 and WASL (By similarity). Interacts (via F-BAR domain) with CAV1 (By similarity). Interacts with TRPV4 (By similarity). {ECO:0000250|UniProtKB:Q9QY17, ECO:0000250|UniProtKB:Q9WVE8, ECO:0000269|PubMed:21693584, ECO:0000269|PubMed:22323287, ECO:0000269|PubMed:23596323}.
Subunit: (Microbial infection) Interacts with ubiquitinated HIV-1 gag (via p6-gag domain); this interaction allows PACSIN2 recruitment to viral assembly sites and its subsequent incorporation into virions. {ECO:0000269|PubMed:29891700}.
Subunit: (Microbial infection) Interacts (via F-BAR domain) with Rous sarcoma virus p2B; this interaction allows PACSIN2 recruitment to viral assembly sites. {ECO:0000269|PubMed:29891700}.
Subunit: (Microbial infection) Interacts (via N-terminus) with Hepatatis C virus (HCV) non-structural protein 5A (via N-terminus); this interaction attenuates protein kinase C alpha (PRKCA)-mediated phosphorylation of PACSIN2 at Ser-313 by disrupting the interaction between PACSIN2 and PRKCA. {ECO:0000269|PubMed:31801866}.
Subcellular location: Cytoplasm {ECO:0000250}. Cytoplasm, cytoskeleton {ECO:0000250}. Cytoplasmic vesicle membrane; Peripheral membrane protein; Cytoplasmic side. Early endosome. Recycling endosome membrane. Cell projection, ruffle membrane; Peripheral membrane protein; Cytoplasmic side. Cell membrane; Peripheral membrane protein; Cytoplasmic side. Cell projection {ECO:0000269|PubMed:31242077}. Membrane, caveola {ECO:0000269|PubMed:22323287}. Note=Detected at the neck of flask-shaped caveolae. Localization to tubular recycling endosomes probably requires interaction with MICALL1 and EHD1.
Tissue specificity: Widely expressed. {ECO:0000269|PubMed:11082044, ECO:0000269|PubMed:11179684}.
Domain: The F-BAR domain forms a coiled coil and mediates membrane- binding and membrane tubulation (PubMed:19549836). Autoinhibition of these functions is mediated by an interaction between the SH3 and F-BAR domains (PubMed:20188097, PubMed:23236520). The F-Bar domain also mediates the binding to the cell actin cytoskeleton through the interaction with CAV-1 (By similarity). {ECO:0000250|UniProtKB:Q9WVE8, ECO:0000269|PubMed:19549836, ECO:0000269|PubMed:20188097, ECO:0000269|PubMed:23236520}.
Domain: (Microbial infection) The SH3 domain is required for the cell- to-cell spreading of HIV-1 virions. {ECO:0000269|PubMed:29891700}.
Ptm: Phosphorylated by casein kinase 2 (CK2). Phosphorylation by PKC probably decreases the membrane binding and tubulation capacities of PACSIN2, thereby modulating the lifetime of caveolae (By similarity). {ECO:0000250|UniProtKB:Q9WVE8}.
Similarity: Belongs to the PACSIN family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.