Cloning, Characterization and Functional Analysis of Two Type 1 diacylglycerol acyltransferases (DGAT1s) from Tetraena mongolica Identification and Sequence Analysis of DGAT2s in Four Plants under the Scenario of Gene Family Cloning and Expression Analysis of Lysophosphatidic Acid Acyltransferase (LPAT) Encoding Gene in Peanut Synthesis of Olive Oil during Olive Development and Ripening Identification of triacylglycerols in coix oil by high performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry