title: Human epidermis is a novel site of phospholipase B expression.
abstract: Phospholipase B (PLB) is an enzyme that displays both phospholipase A(2) and lysophospholipase activities. Analysis of human epidermis homogenates indicated the presence of a 97 kDa PLB protein, as well as a phospholipase A(2) activity, both being enriched in the soluble fraction. Immunolabelling and in situ hybridization experiments showed that this enzyme is expressed in the different layers of epidermis with an accumulation at the dermo-epidermis junction. RT-PCR data indicated that PLB is specifically expressed in natural and reconstructed epidermis. By 3'-RACE-PCR and screening of human genome databases, we obtained a 3600 bp cDNA coding for human PLB highly homologous to already described intestinal brush border PLBs. These data led us to conclude that the soluble PLB corresponds to a proteolytic cleavage of the membrane anchored protein. Altogether, our results provide the first characterization of human PLB which should play an important role in epidermal barrier function.
authors.affiliation: Institut de recherche Pierre Fabre, CERPER/Hôtel Dieu Saint Jacques, F31052 Toulouse, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Maury
authors.forename: Marie Claude
authors.initials: MC
authors.lastname: Prévost
authors.forename: Michel
authors.initials: M
authors.lastname: Nauze
authors.forename: Daniel
authors.initials: D
authors.lastname: Redoulès
authors.forename: Roger
authors.initials: R
authors.lastname: Tarroux
authors.forename: Marie
authors.initials: M
authors.lastname: Charvéron
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Salles
authors.forename: Bertrand
authors.initials: B
authors.lastname: Perret
authors.forename: Hugues
authors.initials: H
authors.lastname: Chap
authors.forename: Ama
authors.initials: A
authors.lastname: Gassama-Diagne
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D015342:DNA Probes; D004817:Epidermis / Q000201:enzymology*; D005230:Fatty Acids, Nonesterified / Q000096:biosynthesis; D006801:Humans; D017403:In Situ Hybridization; D008245:Lysophospholipase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D015342:DNA Probes; D005230:Fatty Acids, Nonesterified; D008245:Lysophospholipase