Hgm1, a novel male-specific gene from Heterodera glycines identified by differential mRNA display

The plant parasitic nematode Heterodera glycines is amphimictic: populations consist of both male and female individuals that reproduce sexually. However, under conditions of environmental stress, unbalanced male and female sex ratios are found. This observation requires an explanation of how sexual fate is determined in these nematodes. As a step towards identifying genes that are differentially regulated between male and female nematodes we have used cDNA differential display to screen for male-specific cDNA sequences. These studies have led to the isolation of a full-length male specific cDNA, Hgm1, that is up regulated in H. glycines males. Sequence analysis of this cDNA reveals that it represents a novel gene which encodes a 49.5 kDa acidic protein with a pI of 4.72 and a predicted 21 amino acid leader sequence. Neither the nucleotide nor the predicted amino acid sequence of this gene show any homology to sequences in the databases suggesting that Hgm1 is a previously uncharacterised gene. Here we report the isolation, molecular characterisation and expression profile of Hgm1.