Naslov
Two classes of 5s rDNA unit arrays of the silver fir, Abies alba Mill.:structure, localization and evolution

Autori
Besendorfer, Višnja ; Krajačić-Sokol, Iva ; Jelenić, Srećko ; Puizina, Jasna ; Mlinarec, Jelena ; Sviben, Tonka ; Papeš, Dražena

Izvornik
Theoretical and applied genetics (0040-5752) 110 (2005); 730-741

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
rDNA units; Abies alba; nontranscribed spacers; phylogeny

Sažetak
The structure and organization of the 5S ribosomal DNA units of the silver fir, Abies alba Mill., as well as their position in the chromosome complement were investigated. PCR amplification of the gene and nontranscribed spacer region (NTS), sequence analysis and Southern hybridization using a homologous probe detected DNA sequences of approximately 550 bp and 700 bp. Sequence analysis of the spacers revealed that the difference in length between the sequences occured in the middle spacer region as a result of the amplification of a 75 bp sequence of the short unit class, which is organized in four 54-68 bp tandem repeats in the long spacer unit. The 5S rDNA transcribing region is 120 bp long and shows high sequence similarity with other gymnosperm species. The comparative analysis of 5´and 3´ flanking sequences of 5S rRNA genes of silver fir and other gymnosperms reveals that A. alba spacer units have the same rate of evolution and are more closely related to Larix and Pseudotsuga than to Pinus and Picea. Southern hybridization and fluorescence in situ hybridization (FISH) to metaphase chromosomes of A. alba suggest that the short and long spacer units are organized as separate tandem arrays at two chromosomal loci, on chromosomes V and XI.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA