title: Identification of a novel human lysophosphatidic acid acyltransferase, LPAAT-theta, which activates mTOR pathway.
abstract: Lysophosphatidic acid acyltransferase (LPAAT) is an intrinsic membrane protein that catalyzes the synthesis of phosphatidic acid (PA) from lysophosphatidic acid (LPA). It is well known that LPAAT is involved in lipid biosynthesis, while its role in tumour progression has been of emerging interest in the last few years. To date, seven members of the LPAAT gene family have been found in human. Here we report a novel LPAAT member, designated as LPAAT-theta, which was 2728 base pairs in length and contained an open reading frame (ORF) encoding 434 amino acids. The LPAAT-theta gene consisted of 12 exons and 11 introns, and mapped to chromosome 4q21.23. LPAAT-theta was ubiquitously expressed in 18 human tissues by RT-PCR analysis. Subcellular localization of LPAAT-theta-EGFP fusion protein revealed that LPAAT-theta was distributed primarily in the endoplasmic reticulum (ER) of COS-7 cells. Furthermore, we found that the overexpression of LPAAT-theta can induce mTOR-dependent p70S6K phosphorylation on Thr389 and 4EBP1 phosphorylation on Ser65 in HEK293T cells.
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Science, Fudan University, Shanghai, 200433, People's Republic of China.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Tang
authors.forename: Jian
authors.initials: J
authors.lastname: Yuan
authors.forename: Xinya
authors.initials: X
authors.lastname: Chen
authors.forename: Xiuting
authors.initials: X
authors.lastname: Gu
authors.forename: Kuntian
authors.initials: K
authors.lastname: Luo
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Wan
authors.forename: Yingli
authors.initials: Y
authors.lastname: Wang
authors.forename: Long
authors.initials: L
authors.lastname: Yu
mesh_terms: D000217:Acyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D004721:Endoplasmic Reticulum / Q000737:chemistry; D015971:Gene Expression Regulation, Enzymologic; D015723:Gene Library; D015894:Genome, Human; D049452:Green Fluorescent Proteins / Q000032:analysis; D006801:Humans; D008969:Molecular Sequence Data; D010766:Phosphorylation; D010802:Phylogeny; D011494:Protein Kinases / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases; D014162:Transfection
chemical_list: D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D000217:Acyltransferases; C018764:2-acylglycerophosphate acyltransferase; D011494:Protein Kinases; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases