Triacylglycerol (TAG) lipase active on triolein, trioctanoin, tributyrin and 1,3-Diolein, but not on phospho- and galactolipids (PubMed:16226259). Involved but dispensable for TAG storage breakdown during seed germination (PubMed:16226259, PubMed:24989044). a triacylglycerol + H2O = a diacylglycerol + a fatty acid + H(+) 1,2,3-tributanoylglycerol + H2O = butanoate + dibutanoylglycerol + H(+) 1,2,3-trioctanoylglycerol + H2O = dioctanoylglycerol + H(+) + octanoate Optimum pH is 6. Active between pH 4-7. Lipid metabolism; glycerolipid metabolism. Expressed in seedlings, roots, leaves, flowers and siliques (PubMed:16226259). Specifically expressed in the epidermis (PubMed:24989044). Accumulates in seeds upon imbibition. Stimulated during seed imbibition (PubMed:24989044). Induced by gibberellins (GAs) and repressed by DELLA proteins (e.g. GAI/RGA2, RGA/RGA1/GRS and RGL2/SCL19) in an ATML1- and PDF2-dependent manner (PubMed:24989044). Upon seed imbibition, increased GA levels in the epidermis reduce DELLA proteins abundance and release, in turn, ATML1 and PDF2 which activate LIP1 expression, thus enhancing germination potential (PubMed:24989044). Belongs to the AB hydrolase superfamily. Lipase family.