Molecular cytogenetic characterization of 55 ribosomal DNA in the harvestman Psathyropus tenuipes (Arachnida : Opiliones)

Abstract

Entire 5S ribosomal DNA (rDNA), including 120 bp of rRNA gene and 142 bp of non-transcribed spacer (NTS) regions of Psathyropus tenuipes (Arachnida, Opiliones, Sclerosomatidae), a harvestman which usually bears several B-chromosomes, was sequenced and mapped on the spermatogonial metaphases using fluorescence insitu hybridization (FISH). The signals of 5S rDNA were detected on the terminal region of one pair of C-bandnegative autosomal chromosomes, showing that the 5S rDNA cluster is localized to A chromosome in this species, but not to B chromosome known as a rDNA carrier in other arthropods.