The stability of telomereless chromosome fragments in adult androgenetic rainbow trout.
The study provides new data on the stability of gamma radiation-induced chromosome fragments of a putative maternal nuclear genome in an androgenetic vertebrate, rainbow trout (Oncorhynchus mykiss Walbaum). The fragments were found in five of 16 examined individuals and they were mostly centromeric parts of metacentric or subtelocentric chromosomes. Chromosome fragments were identical in all cells of a given androgenetic individual, indicating that segregation of chromosome fragments is active from the early cell divisions. Most of the fragments were telomereless, i.e. they had no telomeric sequences on their ends. This shows that telomeres are not necessary for stability of chromosomal structures in a vertebrate genome. In one individual, the interstitial telomeric sites were found in chromosomes, which could be the effect of joining chromosome fragments.
Ocalewicz
K
K
Department of Evolutionary Genetics, University of Warmia and Mazury in Olsztyn, 10-957 Olsztyn, Poland. kocale@diamant.jouy.inra.fr
Babiak
I
I
Dobosz
S
S
Nowaczyk
J
J
Goryczko
K
K
D000818:Animals; D002503:Centromere / Q000235:genetics; D043171:Chromosomal Instability / Q000235:genetics*; D002875:Chromosomes / Q000235:genetics*; D053938:DNA Fragmentation / Q000235:genetics*; D005720:Gamma Rays; D007211:Indoles; D007621:Karyotyping; D017686:Oncorhynchus mykiss / Q000235:genetics*; D010312:Parthenogenesis / Q000235:genetics; D013194:Staining and Labeling; D016615:Telomere / Q000235:genetics
D007211:Indoles; C007293:DAPI