Polynucleotide sequences encoding diacylglycerol acyltransferase genes and the use of these acyltransferases for increased seed storage lipid production and altered fatty acid profiles in oilseed plants are disclosed. Transgenic soybean seed having increased total fatty acid content of at least 20% and altered fatty acids when compared to the total fatty acid content of non-transgenic, null segregant soybean seed are described. Methods for increasing the total fatty acid content of a soybean seed by at least 20% include steps of transformation and selection.