Genomic dynamics of a low-copy-number satellite DNA family in Leptestheria dahalacensis (Crustacea, Branchiopoda, Conchostraca).
The LEP150 satellite DNA (satDNA) family found in Leptestheria dahalacensis (Ruppel, 1837) (Conchostraca) is a low-copy-number satellite with a canonical monomer of 150 bp. Nucleotide variation analyses suggest a 14-bp palindromic region as a possible protein binding site with constraints acting on the whole sequence but a 25-bp variable box. Besides the head-to-tail arrangement of 150 bp monomers, multimers analyses evidenced incomplete monomers, one duplication event, and three inversions. Both observed rearrangements and the higher values of sequence variability scored suggest that rearranged monomers reside in regions with a lower degree of homogenisation efficiency. Sixty-seven percent of the breakpoints occurs at kinkable dinucleotides, thus supporting their role in rearrangements as documented in alphoid satDNA recombination events. Monomers of different lengths may result from crossing over between repeats misaligned through the direct and inverted subrepeats of LEP150 monomers. ANOVA results indicate that the same range of sequence diversity is experienced at the individual and population ranks; therefore, the evolution of the L. dahalacensis satDNA is concerted.
Luchetti
Andrea
A
Dipartimento di Biologia Evoluzionistica Sperimentale, Università di Bologna, Via Selmi 3, Bologna 40126, Italy.
Marino
Alberto
A
Scanabissi
Franca
F
Mantovani
Barbara
B
D000818:Animals; D015139:Blotting, Southern; D003445:Crustacea / Q000235:genetics*; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D004276:DNA, Satellite / Q000235:genetics*; D018628:Gene Dosage; D015321:Gene Rearrangement; D014644:Genetic Variation; D016678:Genome; D008969:Molecular Sequence Data; D010802:Phylogeny; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D017422:Sequence Analysis, DNA
D004276:DNA, Satellite; D004247:DNA