Differences between coding and non-coding regions in the Trichomonas vaginalis genome: an actin gene as a locus model

The sequence of a cloned genomic fragment of Trichomonas vaginalis containi ng a complete actin gene was determined. An uninterrupted open reading fram e of 1128 nucleotides was found that codes for an actin gene. Two overlappe d consensus promoter sequences for T. vaginalis were found 12 nucleotides u pstream the actin initiation codon. In addition to actin, two incomplete op en reading frames were found at the 5' and 3' ends of the clone. These two sequences are expressed and showed similarity to adenylate cyclase genes an d a yeast hypothetical protein. The overall sequence showed a higher G + C content and a lower frequency of repeated sequences in the coding regions w hen compared with the non-coding regions. A similar unequal nucleotide dist ribution was found in various T. vaginalis genes retrieved from data bases. (C) 2001 Elsevier Science B.V. All rights reserved.