An Isolation and Sequence Analysis of the cDNA Encoding Schistosoma japonicum Beta-tubulin

Objective To isolate and identify novel genes from an adult Schistosoma japonicum (Sj) cDNA library, and find new drug targets or vaccine candidates for preventing, controlling and treating schistosomasis. Methods A cDNA library was constructed from Sj (Chinese strain) adult stage. Clones were selected randomly from the cDNA library and were sequenced by using the method of expression sequence Tags (ESTs). Novel genes were acquired by primer-walking. By using bioinformatics,the cDNA sequence encoding Sj beta-tubulin was analyzed, including searching the ORF ,translating the nucleotide to protein sequence ,similarity searches and secondary structure predication. Results Beta-tubulin genes, 1 439 bp and coding for 443 amino acids, was acquired and was submitted to GenBank and to get an accession number that was AY220457. The beta-tubulin gene of S. japonicum and Fasciola hepatica were homologous with an identity of 79%. The academic pI is 9.12, and the antigen determinant is probably from 373 to 396 on the cDNA sequence. Conclusion The full-length cDNA sequence encoding Sj beta-tubulin was obtained, which gave a basis for further functional study of this gene.