title: Patatin-related phospholipase pPLAIIIβ-induced changes in lipid metabolism alter cellulose content and cell elongation in Arabidopsis.
abstract: The release of fatty acids from membrane lipids has been implicated in various plant processes, and the patatin-related phospholipases (pPLAs) constitute a major enzyme family that catalyzes fatty acid release. The Arabidopsis thaliana pPLA family has 10 members that are classified into three groups. Group 3 pPLAIII has four members but lacks the canonical lipase/esterase consensus catalytic sequences, and their enzymatic activity and cellular functions have not been delineated. Here, we show that pPLAIIIβ hydrolyzes phospholipids and galactolipids and additionally has acyl-CoA thioesterase activity. Alterations of pPLAIIIβ result in changes in lipid levels and composition. pPLAIIIβ-KO plants have longer leaves, petioles, hypocotyls, primary roots, and root hairs than wild-type plants, whereas pPLAIIIβ-OE plants exhibit the opposite phenotype. In addition, pPLAIIIβ-OE plants have significantly lower cellulose content and mechanical strength than wild-type plants. Root growth of pPLAIIIβ-KO plants is less sensitive to treatment with free fatty acids, the enzymatic products of pPLAIIIβ, than wild-type plants; root growth of pPLAIIIβ-OE plants is more sensitive. These data suggest that alteration of pPLAIIIβ expression and the resulting lipid changes alter cellulose content and cell elongation in Arabidopsis.
authors: Department of Biology, University of Missouri, St. Louis, Missouri 63121, USA.
authors: Maoyin
authors: M
authors: Li
authors: Sung Chul
authors: SC
authors: Bahn
authors: Liang
authors: L
authors: Guo
authors: William
authors: W
authors: Musgrave
authors: Howard
authors: H
authors: Berg
authors: Ruth
authors: R
authors: Welti
authors: Xuemin
authors: X
authors: Wang
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D049108:Cell Enlargement; D002462:Cell Membrane / Q000378:metabolism; D002482:Cellulose / Q000032:analysis*; D005230:Fatty Acids, Nonesterified / Q000032:analysis / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D050356:Lipid Metabolism; D008969:Molecular Sequence Data; D010741:Phospholipases A / Q000235:genetics / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D019441:Plant Epidermis / Q000254:growth & development; D018515:Plant Leaves / Q000254:growth & development; D018517:Plant Roots / Q000201:enzymology / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000254:growth & development
chemical_list: D029681:Arabidopsis Proteins; D005230:Fatty Acids, Nonesterified; D010743:Phospholipids; D002482:Cellulose; D010741:Phospholipases A