This invention relates to an isolated nucleic acid fragment encoding a diacylglycerol acyltransferase. The invention also relates to the construction of a chimeric gene encoding all or a portion of the diacylglycerol acyltransferase, in sense or antisense orientation, wherein expression of the chimeric gene results in production of altered levels of the diacylglycerol acyltransferase in a transformed host cell.