Naslov
An overview of repetitive DNA sequences from the bivalve Donax trunculus

Autori
Šatović, Eva ; Plohl, Miroslav

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
6th Congress of the European Malacological Societies - Abstract book / - , 2011, 110-110

Skup
6th Congress of the European Malacological Societies

Mjesto i datum
Vitoria-Gasteiz, Španjolska, 18.07.2011. - 22.07.2011

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
satellite DNA; mobile elements; bivalv; Donax trunculus

Sažetak
Genome of the clam Donax trunculus harbors 8 already described low-abundant (up to 2%) satellite DNA sequences. In order to amend our knowledge about composition of repetitive DNAs in this organism, genomic libraries were constructed and recombinant colonies were screened by hybridization with complete genomic DNA of D. trunculus used as a probe. Extracted sequences were categorized into six groups, with respect to different types of repetitive DNA. First group harbored genomic fragments consisting of tandemly repeated satellite DNA monomers only. In the second group, satellite DNAs were attached to non- repetitive and yet uncharacterized sequences of the mollusk genome. Few clones from these two groups were identified as members of a BIV160 satellite DNA family, a large group of sequences widely spread in bivalve species and related to the MITE-like mobile element Pearl of oysters. BIV160 family is about 540 million years old, thus representing the oldest described satellite DNA. Because of this interesting feature these sequences were further investigated by constructing specific primers which yielded 42 new satellite monomers. Few other clones from the second group of sequences were found to contain some of the previously characterized low-copy satellites (DTHS1, DTHS3 and DTE). One clone from the same group contained yet undescribed satellite DNA that was further analysed by constructing specific primers and extracting 67 additional monomers. New satellite shows structural similarity to CvG mobile element from Crassostrea virginica that is also a part of the same aforementioned Pearl mobile element family of oysters. Next three groups of genomic fragments retrieved by this method showed similarity to different types of mobile elements ; one to different families of DNA transposons and the other two to LTR and non-LTR retrotransposons. The last group of sequences is comprised from more than one type of repetitive DNA, containing different combinations of elements found in the former 5 groups. Obtained results show coexistence of a variety of repetitive DNA sequences in the D. trunculus genome, without predominance of a particular type, while similarities among them indicate the role of transposable elements in formation and spreading of satellite repeats.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA