The 5S rDNA high dynamism in Diplodus sargus is a transposon-mediated mechanism. Comparison with other multigene families and Sparidae species.
There has been considerable discussion in recent years on the evolution of the tandemly repeated multigene families, since some organisms show a concerted model whereas others show a birth-and-death model. This controversial subject extends to several species of fish. In this study, three species of the Sparidae family (Pagrus pagrus, P. auriga and Diplodus sargus) and an interspecific hybrid (P. pagrus (♀) × P. auriga (♂)) have been studied at both molecular and cytogenetic level, taking three different multigene families (5S rDNA, 45S rDNA and U2 snDNA). Results obtained with the 5S rDNA in P. pagrus and P. auriga are characterized by a considerable degree of conservation at the two levels; however, an extraordinary variation was observed in D. sargus at the two levels, which has never been found in other fishes studied to date. As a consequence of this, the evolutionary model of the multigene families is discussed considering the results obtained and others from the bibliography. The result obtained in the hybrid allowed the recombination frequency in each multigene family to be estimated.
Laboratorio de Genética, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Polígono Río San Pedro, Puerto Real, Cádiz, Spain.
Manuel A
MA
Merlo
Ismael
I
Cross
Manuel
M
Manchado
Salvador
S
Cárdenas
Laureana
L
Rebordinos
D000818:Animals; D004251:DNA Transposable Elements / Q000502:physiology*; D004275:DNA, Ribosomal / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D018507:Gene Expression Regulation, Developmental; D049810:Genetic Speciation; D014644:Genetic Variation / Q000502:physiology; D008297:Male; D005810:Multigene Family / Q000235:genetics; D010473:Perciformes / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D012341:RNA, Ribosomal, 5S / Q000235:genetics*; D013045:Species Specificity
D004251:DNA Transposable Elements; D004275:DNA, Ribosomal; D012341:RNA, Ribosomal, 5S