Contributes to cuticular wax and suberin biosynthesis. Involved in both decarbonylation and acyl-reduction wax synthesis pathways. Elongase condensing enzyme mostly active with saturated fatty acids, especially with 16:0, 16:1, 18:0, and 20:0. Mediates the synthesis of VLCFAs from 20 to 26 carbons in length (e.g. C20:1, C20, C22, C24 and C26). a very-long-chain acyl-CoA + H(+) + malonyl-CoA = a very-long-chain 3-oxoacyl-CoA + CO2 + CoA Inhibited by K3 herbicides such as alachlor, allidochlor, anilofos, cafenstrole, fentrazamide and flufenacet (PubMed:15277688). Strongly inhibited by metazachlor and mefluidide (PubMed:22284369). Lipid metabolism; fatty acid biosynthesis. Ubiquitous (PubMed:10074711). Expressed in siliques, flowers, leaves and stems. Barely detected in roots (PubMed:18465198). Repressed by herbicides such as flufenacet and benfuresate (PubMed:12916765). Down-regulated by darkness and low temperature, and up-regulated by salt, drought and osmotic stress (PubMed:18465198). Plants have thinner stems with an altered wax composition, and are more sensitive to dehydration. Belongs to the thiolase-like superfamily. Chalcone/stilbene synthases family. It is uncertain whether Met-1 or Met-9 is the initiator. Truncated N-terminus.