A NEWLY FORMED TELOMERE IN ASCARIS-SUUM DOES NOT EXERT A TELOMERE POSITION EFFECT ON A NEARBY GENE

During the process of chromatin diminution Ascaris suum (formerly name d Ascaris lumbricoides var. suum), developmentally regulated chromosom al fragmentation and new telomere addition occur within specific chrom osomal breakage regions (CBRs). The DNA sequences flanking one of thes e CBRs (CBR-1) were analyzed, and two protein-encoding genes were foun d on either side. The noneliminated gene, agp-1, whose AUG start codon is located within approximately 2 kb of the boundary of CBR-1 encodes a putative GTP-binding protein which is structurally related to eukar yotic and prokaryotic elongation factors. Northern (RNA) blot analyses revealed that transcripts of this gene are present at all development al stages, suggesting that the massive chromosomal rearrangements asso ciated with the process of chromatin diminution have no influence on a gp-1 expression. This demonstrates that addition of new telomeres in C BR-1 does not result in a telomeric position effect, a phenomenon prev iously described in Saccharomyces cerevisiae.