Characterisation of the beta-tubulin gene of Cylicocyclus nassatus

mRNA and genomic DNA were isolated from adult Cylicocyclus nassatus, and th e mRNA was reverse transcribed. The cDNA was PCR amplified using degenerate primers designed according to the alignment of the beta-tubulin amino acid sequences of other species. To complete the coding sequence, the 3' end wa s amplified with the 3' RACE, and for amplification of the 5' end the SL1-p rimer was used, The cDNA of the beta-tubulin gene of C. nassatus spans 1429 bp and encodes a protein of 448 amino acids. Specific primers were develop ed from the cDNA sequence to amplify the genomic DNA sequence and to analys e the genomic organisation of the beta-tubulin gene. The complete sequence of the genomic DNA of the beta-tubulin gene of C. nassatus has a size of 26 52 bp and is organised into nine exons and eight introns. The identities wi th the exons of the gru-1 beta-tubulin gene of Haemonchus contortus range b etween 79% and 97%. (C) 1999 Australian Society for Parasitology Inc. Publi shed by Elsevier Science Ltd. All rights reserved.