High impact information on LRO1

• Phospholipid:diacylglycerol acyltransferase: an enzyme that catalyzes the acyl-CoA-independent formation of triacylglycerol in yeast and plants [1].
• The substrate specificity of this PDAT depends on the head group of the acyl donor, the acyl group transferred, and the acyl chains of the acceptor DAG [1].
• We further found that PDAT activity also is present in yeast microsomes [1].
• Using a dga1lro1are1are2 quadruple mutant transformed with plasmids bearing inducible DGA1, LRO1, or ARE2 we demonstrate that TAG synthesis contributes more efficiently to lipid particle proliferation than synthesis of STE [2].
• This novel type of long-chain acyl-CoA acyltransferase is not related to known acyltransferases including the WS from jojoba (Simmondsia chinensis), the DGAT1 or DGAT2 families present in yeast, plants, and animals, and the phospholipid:diacylglycerol acyltransferase catalyzing TAG formation in yeast and plants [3].

Biological context of LRO1

• In vitro microsomal assays determined that Lro1 mediated the esterification of diacylglycerol using phosphatidylcholine as the acyl donor [4].
• A search of the Arabidopsis genome database identified the protein encoded by the At5g13640 gene as the closest homolog to the yeast PDAT (28% amino acid identity) [5].
• Acylation of DAG to yield TAG is catalyzed mainly by the two yeast proteins Dga1p and Lro1p, which utilize acyl-CoA or phosphatidylcholine, respectively, as acyl donors [6].

Associations of LRO1 with chemical compounds

• The residual triglyceride biosynthesis that persists in the LRO1 deletion strain is mainly acyl-CoA-dependent and mediated by a gene that is structurally distinct from the previously identified mammalian diacylglycerol acyltransferase [4].
• A new pathway for triacylglycerol biosynthesis involving a phospholipid:diacylglycerol acyltransferase (PDAT) was recently described (Dahlqvist A, Stahl U, Lenman M, Banas A, Lee M, Sandager L, Ronne H, Stymne S, [2000] Proc Natl Acad Sci USA 97: 6487-6492) [5].

References