Comment type | Description |
Alternative Products | Event=Alternative splicing; Named isoforms=3; Name=1; IsoId=Q8BJ56-1; Sequence=Displayed; Name=2; IsoId=Q8BJ56-2; Sequence=VSP_026424; Note=No experimental confirmation available.; Name=3; IsoId=Q8BJ56-3; Sequence=VSP_026422, VSP_026423; Note=No experimental confirmation available.; |
Catalytic Activity | Triacylglycerol + H(2)O = diacylglycerol + a carboxylate. {ECO:0000269|PubMed:16679289}. |
Developmental Stage | Increased expression when preadipocytes are induced to differentiate to adipocytes. Not detected in proliferating or confluent preadipocytes. {ECO:0000269|PubMed:15337759, ECO:0000269|PubMed:15550674, ECO:0000269|PubMed:16150821, ECO:0000269|PubMed:16705060}. |
Disruption Phenotype | Mice show increased adipose mass and triacylglycerol deposition in multiple tissues. They accumulate large amounts of lipid in the heart, causing cardiac dysfunction and premature death. {ECO:0000269|PubMed:16675698}. |
Enzyme Regulation | Stimulated by PKA-dependent PLIN phosphorylation. {ECO:0000269|PubMed:15550674, ECO:0000269|PubMed:17074755, ECO:0000269|PubMed:17114792}. |
Function | Catalyzes the initial step in triglyceride hydrolysis in adipocyte and non-adipocyte lipid droplets. Also has acylglycerol transacylase activity. May act coordinately with LIPE/HLS within the lipolytic cascade. Regulates adiposome size and may be involved in the degradation of adiposomes. May play an important role in energy homeostasis. May play a role in the response of the organism to starvation, enhancing hydrolysis of triglycerides and providing free fatty acids to other tissues to be oxidized in situations of energy depletion. {ECO:0000269|PubMed:15337759, ECO:0000269|PubMed:15550674, ECO:0000269|PubMed:16150821, ECO:0000269|PubMed:16675698, ECO:0000269|PubMed:16679289, ECO:0000269|PubMed:17074755}. |
Induction | Transiently induced during fasting. cAMP and glucagon may not be involved in the induction during fasting. Induced by dexamethasone. Down-regulated by insulin, isoprotenerol and TNF- alfa. Expression is not affected by glucose and by growth hormone. Expression is reduced in fasted leptin deficient mouse (ob/ob), an obese mouse model. Expression is not affected in fed ob/ob mouse. {ECO:0000269|PubMed:15337759, ECO:0000269|PubMed:16009485, ECO:0000269|PubMed:16150821, ECO:0000269|PubMed:16380488, ECO:0000269|PubMed:16705060}. |
Pathway | Glycerolipid metabolism; triacylglycerol degradation. |
Ptm | Phosphorylation at Ser-406 by PKA is increased during fasting and moderate intensity exercise, and moderately increases lipolytic activity. {ECO:0000269|PubMed:15550674, ECO:0000269|PubMed:22733971}. |
Sequence Caution | Sequence=BAB22643.1; Type=Frameshift; Positions=301, 317, 460; Evidence={ECO:0000305}; |
Similarity | Contains 1 patatin domain. {ECO:0000305}. |
Subcellular Location | Lipid droplet. Cell membrane; Single-pass type II membrane protein. |
Subunit | Interacts with ABHD5; this association stimulates PNPLA2 triglyceride hydrolase activity. Interacts with SERPINF1; interacts at one site of interaction (By similarity). Despite a colocalization in lipid droplets, it probably does not interact with PLIN. Interacts with PLIN5; prevents interaction with ABHD5. {ECO:0000250, ECO:0000269|PubMed:16679289, ECO:0000269|PubMed:17189257, ECO:0000269|PubMed:21148142, ECO:0000269|PubMed:21393244}. |
Tissue Specificity | Expressed at high levels in white and brown adipose tissue, and to a lesser degree in testis and cardiac muscle. Barely detected in liver, spleen, thymus, kidney, skeletal muscle, and brain. Among the white adipose depots, gonadal fat showed the highest level of expression compared with inguinal and renal white adipose tissues. {ECO:0000269|PubMed:15337759, ECO:0000269|PubMed:15550674, ECO:0000269|PubMed:16150821, ECO:0000269|PubMed:16705060}. |