Characterisation of guanylyl cyclase genes in the soybean cyst nematode, Heterodera glycines.
Parasitism by the soybean cyst nematode, Heterodera glycines, has become one of the major limiting factors in soybean production world-wide. A partial HG-gcy-1 cDNA clone was obtained by screening a H. glycines cDNA library with a probe derived from the HG-gcy1 genomic sequence, and HG-gcy-1 full-length cDNA was obtained by nested PCR and 5' rapid amplification of cDNA ends (5' RACE). Two additional, full-length guanylyl cyclase cDNA clones from H. glycines, named HG-gcy-2 and HG-gcy-3, were recovered directly by screening the H. glycines cDNA library with a probe derived from sequence of the HG-gcy-1 catalytic domain. The encoded proteins of all three HG-gcy genes had an extracellular ligand-binding domain, a single membrane-spanning domain, an intracellular protein kinase-like domain, and a guanylyl cyclase catalytic domain. The three HG-GCY proteins had conserved cysteine residues to form disulfide bridges within the extracellular domain similar to the predicted ligand-binding domains of other known membrane-bound guanylyl cyclases. mRNA in situ hybridisation detected the expression of HG-gcy-1 and HG-gcy-2 transcripts in specific and different sensory neurons within H. glycines specimens. HG-gcy-3 transcripts were not localised in H. glycines specimens by in situ hybridisation. The discovery of the three guanylyl cyclase genes in H. glycines is the first of its kind in a plant-parasitic nematode and may be representative of a conserved gene family used for chemosensory recognition in parasitic nematodes.
Yan
Yitang
Y
Department of Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA.
Davis
Eric L
EL
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D006162:Guanylate Cyclase / Q000737:chemistry / Q000235:genetics*; D017403:In Situ Hybridization; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D009348:Nematoda / Q000201:enzymology* / Q000235:genetics; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D013025:Glycine max / Q000469:parasitology*
D018509:DNA, Helminth; D007527:Isoenzymes; D012333:RNA, Messenger; D006162:Guanylate Cyclase