Naslov
Satellite DNAs in Tenebrionid beetles - 15 years of research

Autori
Plohl, Miroslav

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

Izvornik
45 years of molecular biology in Croatia, 50 years of double helix / Ambriović-Ristov, Andreja ; Brozović, Anamaria - Zagreb : Farmaceutsko-biokemijski fakultet Sveučilišta u Zagrebu, 2003, 14-15

Skup
2nd scientific symposium with international participation: 45 years of molecular biology in Croatia, 50 years of double helix

Mjesto i datum
Zagreb, Hrvatska, 20.11.2003. - 21.11.2003

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
repetitive sequences; Coleoptera; heterochromatin; centromere; evolution

Sažetak
Noncoding, tandemly repeated sequences or satellite DNAs exist in every eukaryotic genome, as major DNA component of heterochromatin. Although these sequences comprise functionally important chromosomal regions, like centromeres, they represent the least known part of the genome. Due to the repetitive nature of satellite DNA components, it is extremely difficult to assess heterochromatic regions by sequencing strategies, and they are excluded from genome projects. The work on analysis of satellite DNAs on almost 30 insect species from the family Tenebrionidae revealed beetles as convenient model system. Typically, one or two satellites are highly abundant, building up to 50% of DNA of each species. Major satellites of one species are distributed among related species, but as low copy repeats that represent <0.05% of genomic DNA. This is the first experimental evidence of the library hypothesis, that a group of related species shares a common set of satellite repeats. Tenebrionid satellites cannot be related by their nucleotide sequences. However, these sequences often show similar structural characteristics, like bent DNA helix axis, or common patterns in distribution of nucleotides. These characteristics may be important for association with specific protein components and condensation of heterochromatin. Since satellites within a library share structural characteristics, they can perform a similar role and can easily replace each other. All examined satellites are located in centromeric heterochromatin of all chromosomes of the complement, and probably comprise a region of functional centromere. Rapid changes of satellite components in centromeric heterochromatin might affect the fecundity in crosses between individuals and raise a reproductive barrier that would act as a trigger in the speciation process.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA