Genomic organization of ribosomal DNA and related sequences inTriturus

✍ Scribed by Francesca Andronico; Stefania Lucchini; Irma Nardi; Marzia Giuliani; Rocco Savino

• Publisher: Springer
• Year: 1988
• Tongue: English
• Weight: 341 KB
• Volume: 1
• Category: Article
• ISSN: 0920-9069
• DOI: 10.1007/bf00146822

✦ Synopsis

The ribosomal RNA genes of Triturus vulgaris meridionalis are clustered at variable and often multiple chromosomal loci. The rDNA repeats exhibit only a limited and discrete length heterogeneity whicla is accounted for by the non-transcribed spacer (NTS). Interestingly, sequences homologous to the NTS are clustered outside the ribosomal loci. Clones containing such 'non ribosomal sequences' have been isolated from a genomic library of T. v. meridionalis and analyzed by restriction mapping. These sequences appear to consist mostly of repetitive Barn HI fragments ranging from 500 bp to 1000 bp. The Barn HI fragments are internally repetitious and highly homologous to each other.