Characterisation and developmental expression of a chitinase gene in Heterodera glycines.
A chitinase full-length cDNA (designated Hg-chi-1) was isolated from a Heterodera glycines oesophageal gland cell-specific long-distance PCR cDNA library. The cDNA hybridised to genomic DNA of H. glycines in Southern blots. The Hg-chi-1 cDNA contained an open reading frame encoding 350 amino acids with the first 23 amino acids being a putative signal peptide for secretion. Hg-CHI-1 contained a chitinase 18 family catalytic domain, and chitinolytic activity of recombinant Hg-CHI-1 was confirmed in glycol-chitin substrate gel electrophoresis. In situ mRNA hybridisation analyses showed that transcripts of Hg-chi-1 accumulated specifically in the subventral oesophageal gland cells of parasitic stages of H. glycines, but Hg-chi-1 expression was not detected in eggs or hatched pre-parasitic second-stage juveniles, suggesting that this chitinase does not have a role in egg hatching of H. glycines. The biological function of Hg-CHI-1 in H. glycines remains to be determined.
Department of Plant Pathology, University of Georgia, Athens, GA 30602-7274, USA.
Bingli
B
Gao
R
R
Allen
Tom
T
Maier
Jeff P
JP
McDermott
Eric L
EL
Davis
Thomas J
TJ
Baum
Richard S
RS
Hussey
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002688:Chitinases / Q000032:analysis / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis / Q000302:isolation & purification; D018509:DNA, Helminth / Q000235:genetics; D015870:Gene Expression; D017238:Genes, Helminth; D016678:Genome; D015801:Helminth Proteins / Q000235:genetics* / Q000378:metabolism*; D017403:In Situ Hybridization; D008018:Life Cycle Stages; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014431:Tylenchoidea / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism
D018076:DNA, Complementary; D018509:DNA, Helminth; D015801:Helminth Proteins; D011994:Recombinant Proteins; D002688:Chitinases