CHS2, a chitin synthase gene from the oomycete Saprolegnia monoica.
PCR was used to amplify fragments corresponding to the chitin synthase (CHS) genes from the Oomycetes Saprolegnia monoica, Phytophthora capsici and Achlya ambisexualis, utilizing as primers, oligonucleotides designed from the conserved region of CHS genes of chitinous fungi. Chitin synthase homologues were found in the three cellulosic fungi. The chitin synthase 2 gene (CHS2) from S. monoica was cloned, sequenced and characterized. The amino acid sequence deduced from the CHS2 genomic DNA revealed several domains, corresponding to the catalytic domains and polypeptide signatures, of high identity with CHS genes from chitinous fungi. Existence of a CHS gene family in S. monoica was supported by the identification of two CHS sequences among the PCR products, the localization of CHS homologues on two chromosomes, and the detection of two transcripts in mycelia and protoplasts. Polyclonal anti-chitin synthase antibodies raised against the N-terminal and the neutral fragments of the CHS2 products revealed, respectively, two and four proteins in membrane fractions and a truncated active form in entrapped product. The overall comparison of the structure and organization of CHS genes indicates that in spite of their divergent evolution, Oomycetes and chitinous fungi have evolved with conserved chitin synthase systems.
Mort-Bontemps
Maryline
M
Laboratoire de Biologie Cellulaire Fongique, Centre de Génétique Moléculaire et Cellulaire, UMR CNRS 5534, Universite Lyon I, 43 Bd du 11 Novembre 1918, Baâtiment 405, 69622 Villeurbanne Cedex, France.
Gay
Lucien
L
Laboratoire de Biologie Cellulaire Fongique, Centre de Génétique Moléculaire et Cellulaire, UMR CNRS 5534, Universite Lyon I, 43 Bd du 11 Novembre 1918, Baâtiment 405, 69622 Villeurbanne Cedex, France.
Févre
Michel
M
Laboratoire de Biologie Cellulaire Fongique, Centre de Génétique Moléculaire et Cellulaire, UMR CNRS 5534, Universite Lyon I, 43 Bd du 11 Novembre 1918, Baâtiment 405, 69622 Villeurbanne Cedex, France.
D000595:Amino Acid Sequence; D001483:Base Sequence; D002687:Chitin Synthase / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D015870:Gene Expression / Q000235:genetics; D005800:Genes, Fungal / Q000235:genetics*; D007120:Immunochemistry; D008969:Molecular Sequence Data; D009868:Oomycetes / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D002687:Chitin Synthase