Stage-specific gene expression in Angiostrongylus cantonensis: characterisation and expression of an adult-specific gene

We have previously used differential mRNA display to identify and clone a range of cDNAs derived from genes expressed in only one developmental stage of Angiostrongylus cantonensis. In this paper we report the characterisation of a gene designated Ac-fmp-1 and its product, expressed only in the adult stage. Full length cDNA of 1.5 kb terminates at the 5' end with the conserved nematode spliced leader (SL) sequence and contains one open reading frame coding for a putative protein of 417 amino-acids. The recombinant protein expressed from this open reading frame is antigenic in the infected host and polyclonal antibodies raised against the recombinant protein recognize a 66 kDa protein present only in adult female worms. This protein localises to the muscle cell membranes adjacent to the pseudocoelom. Nine kb of genomic DNA has been amplified by polymerase chain reaction and 7 kb has been cloned and sequenced. This sequence includes 1.5 kb of 5' flanking region and 5.5 kb of the Ac-fmp-1 gene sequence. in this sequence, corresponding to approximately 0.8 kb of the cDNA, the exon/intron pattern has been determined. (C) 1997 Elsevier Science Ireland Ltd.