Survey of the Botrytis cinerea chitin synthase multigenic family through the analysis of six euascomycetes genomes.
We describe a strategy for systematic amplification of chitin synthase genes (chs) in the filamentous ascomycetes plant-pathogen Botrytis cinerea using PCR with multiple degenerate primers designed on specific and conserved sequence motifs. Eight distinct chs genes were isolated, named Bcchs I, II, IIIa, IIIb, IV, V, VI and VII. They probably constitute the entire chs multigenic family of this fungus, as revealed by careful analysis of six euascomycetes genomes. Bcchs I, IIIa, IIIb, IV and VI genes were subjected to DNA walking and their deduced amino acid sequences were compared by hydrophobic cluster analysis (HCA) to localize putative residues critical for CHS activity. HCA also enabled us to highlight three different transmembrane topologies of the CHS membranous isoenzymes. We found that the N-terminal region of the BcCHSI isoenzyme, and its orthologues in other euascomycetes, probably contain folded peptide motifs with conserved tyrosine residues. Their putative role is discussed. The BcCHSVII isoenzyme appeared to belong to a new class of CHS orthologues that was demonstrated by phylogenetic study to branch apart from division 1 and 2 of CHS.
Choquer
Mathias
M
UMR 7613 CNRS/Université Paris VI, 4 place Jussieu, 75005 Paris, France.
Boccara
Martine
M
Gonçalves
Isabelle R
IR
Soulié
Marie-Christine
MC
Vidal-Cros
Anne
A
D020121:5' Untranslated Regions; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000502:physiology; D020171:Botrytis / Q000201:enzymology* / Q000235:genetics; D002384:Catalysis; D002687:Chitin Synthase / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D004271:DNA, Fungal / Q000032:analysis; D005800:Genes, Fungal; D016681:Genome, Fungal; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
D020121:5' Untranslated Regions; D000596:Amino Acids; D004271:DNA, Fungal; D002687:Chitin Synthase