Enhances the transfer of lipids between membranes in vitro (PubMed:15456765). Active on phosphatidylcholine (PC), 1-palmitoyl 2-oleoyl phosphatidylcholine (POPC) and ergosterol, and, to a lower extent, dimyristoyl phosphatidic acid, stigmasterol, desmosterol, beta-sitosterol and steryl glucoside (PubMed:15456765). Inactive or poorly active on palmitic acid, stearoyl-coenzyme A, cholesterol, glucosylceramide and ceramide (PubMed:15456765). Required during seeds and seedlings development (PubMed:18687588). Expressed in most tissues including seedlings, cotyledons, inflorescence, leaves, stems, roots, siliques and flower buds, with the highest levels in floral tissues and in maturing seeds. In seeds, observed mainly in the endosperm and the embryo (PubMed:18687588). In seedlings, detected in vascular tissues and hydathodes of cotyledons (PubMed:18687588). Later expressed in trichomes of rosette leaves (PubMed:18687588). In flowers, accumulates in the receptacles, in vascular tissues of sepals and petals, in the style and stigma of the carpels, and in anthers, filaments, and pollen (PubMed:18687588). Also present in siliques funiculi (PubMed:18687588). Accumulates at higher levels in dark-grown seedlings (PubMed:18687588). Induced by sucrose (PubMed:18687588). Altered seed morphology and delayed seed germination as well as inhibited root elongation in the dark; an exogenous carbon source is required to recover from the delayed seedling establishment. Reduced levels of glutamine, pyroglutamic acid, aspartate, beta-alanine, fumaric acid, glyceraldehyde and ribose, but increased accumulation of serine, glycine, asparagine, 3-cyanoalanine and 5-methylthiopentanitrile.