Chromosome analysis and molecular characterization of highly repeated DNAsin the aphid Acyrthosiphon pisum (Aphididae, Hemiptera)

Despite the interest in aphid biology, information on chromatin organizatio n of their holocentric chromosomes is still limited to few species. In orde r to fill this gap, we have performed an extensive survey on pea aphid mito tic chromosomes using both classical and molecular cytogenetic techniques. Our results after silver, CMA(3) and DAPI-staining, C-banding and fluoresce nt in situ hybridization (FISH) using 28S rDNA and 5S rDNA as probes eviden ced a tendency of repetitive DNAs to be concentrated on the X chromosomes. FISH experiments with the telomeric probe (TTAGG)(n) revealed bright hybrid ization signals on each telomere of all Acyrthosiphon pisum chromosomes. No interstitial signals were seen.