Microsatellite distribution on sex chromosomes at different stages of heteromorphism and heterochromatinization in two lizard species (Squamata: Eublepharidae: Coleonyx elegans and Lacertidae: Eremias velox)

0381524 - ÚŽFG 2013 RIV GB eng J - Journal Article
Pokorná, Martina - Kratochvíl, L. - Kejnovský, Eduard
Microsatellite distribution on sex chromosomes at different stages of heteromorphism and heterochromatinization in two lizard species (Squamata: Eublepharidae: Coleonyx elegans and Lacertidae: Eremias velox).
B M C Genetics. Roč. 12, č. 1 (2011), s. 90-96. ISSN 1471-2156. E-ISSN 1471-2156
R&D Projects: GA ČR GAP506/10/0718; GA ČR(CZ) GAP305/10/0930
Institutional research plan: CEZ:AV0Z50450515; CEZ:AV0Z50040702
Keywords : repeated dna-sequences * Y-chromosome * determining mechanisms
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.475, year: 2011

The accumulation of repetitive sequences such as microsatellites during the differentiation of sex chromosomes has not been studied in most squamate reptiles (lizards, amphisbaenians and snakes), a group which has a large diversity of sex determining systems. It is known that the Bkm repeats containing tandem arrays of GATA tetranucleotides are highly accumulated on the degenerated W chromosomes in advanced snakes. Similar, potentially homologous, repetitive sequences were found on sex chromosomes in other vertebrates. Using FISH with probes containing all possible mono-, di-, and tri-nucleotide sequences and GATA, we studied the genome distribution of microsatellite repeats on sex chromosomes in two lizard species (the gecko Coleonyx elegans and the lacertid Eremias velox) with independently evolved sex chromosomes. The gecko possesses heteromorphic euchromatic sex chromosomes, while sex chromosomes in the lacertid are homomorphic and the W chromosome is highly heterochromatic. Our aim was to test whether microsatellite distribution on sex chromosomes corresponds to the stage of their heteromorphism or heterochromatinization. Moreover, because the lizards lie phylogenetically between snakes and other vertebrates with the Bkm-related repeats on sex chromosomes, the knowledge of their repetitive sequence is informative for the determination of conserved versus convergently evolved repetitive sequences across vertebrate lineages.
Permanent Link: http://hdl.handle.net/11104/0211975