A variety of plants are natural resources for oil and are capable of synthesizing and storing large amounts of oil in the form of triacylglycerols (TAGs). The composition of TAG and the organs and tissue types in which it is accumulated varies widely among plants. Although the biochemical steps involved in TAG synthesis are highly conserved, the tissue-specific regulation of TAG content and composition remains unclear. In avocado (Persea americana), a basal angiosperm, TAG is exclusively accumulated in mesocarp tissue with ~60-70% of oil by dry weight, of which ~80% is composed of oleic acid. Our research is focused on characterization of acyltransferases and their transcriptional regulators involved in TAG synthesis in mesocarp of avocado, as nonseed tissues are significant contributors to world oil production.
Specifically, we are focused on cloning and biochemical characterization of avocado acyl-CoA:diacylglycerol acyltransferase (DGAT1 - acyl-CoA dependent enzyme) and phospholipid:diacylglycerol acyltransferase (PDAT1 - acyl-CoA independent), and PaWRI1, PaWRI2 and PaWRI3, using heterologous/transient expression systems.