Sažetak | U mnogim vrstama životinja (i ljudi) otkrivene su stotine sekvenci koje potječu od
insercija mtDNA u nuklearni genom. Danas se te sekvence zovu numt-ovi (nuklearne
mitohondrijske DNA) ili mitohondrijski pseudogeni. Međutim, distribucija numt-ova kod
goveda se tek odnedavno počela istraživati. Cilj rada bio je identificirati i istražiti učestalost
pojave segmenata mitohondrijske DNA u genomu jezgre goveda. Za istraživanje su korištene
33 sekvence iz projekta MitoTAUROmics te referentni kromosomi i mtDNA Bos taurusa i Bos
indicusa koji su dostupni u javnim bazama podataka. Usporedbe su se radile uz pomoć
BLAST+ softvera, a poravnanje sekvenci se radilo pomoću MEGA 7.0.26. softvera. Pronađeno
je ukupno 156 potencijalnih numt-ova, od kojih je 86 potvrđeno. Iako su više kromosoma Bos
indicusa imali podudaranja sa traženim sekvencama, sama duljina segmenata je bila veća kod
Bos taurusa. Najduži numt ima 6393 pb, dok najkraći 27 pb. Podudarnost između numt-ova i
mtDNA varira od 70% do 100%. Ukupna duljina fragmenata kod Bos taurusa je bila 57189 pb,
što je 3,5 puta dulje od ukupne duljine mitogenoma. Duljina fragmenata Bos indicusa je 30609
pb, što je 1,9 puta dulje od ukupne duljine mitogenoma. U mtDNA Bos taurusa identificirano
je 5 potpunih gena koji kodiraju proteine, a to su 12s rRNA, COX1, COX2, COX3, ATP6 koji
su pronađeni u 9 numt-ova. Kod Bos indicusa identificirano je 6 potpunih gena: ND3, ND6,
ATP6, ATP8, COX3, ND4L u 5 numt-ova. Većina ostalih numt-ova kodira mt-tRNA gene. Iako
su otkriveni geni koji kodiraju proteine, potrebna su daljnja istraživanja radi provjere
funkcionalnosti numt-ova koji kodiraju mt-tRNA molekule. |
Sažetak (engleski) | In many animal species (and humans), hundreds of sequences, which originated from the
insertion of mtDNA into the nuclear genome, have been discovered. Today, these sequences
are called numts (nuclear mitochondrial DNAs) or mitochondrial pseudogenes. However, the
distribution of cattle numts has only recently begun to be investigated. The aim of the study
was to identify and investigate the incidence of mitochondrial DNA segments in the cattle
nuclear genome. For this study 33 mitochondrial sequences, which were available from the
MitoTAUROmics project and reference chromosomes and mtDNA of Bos taurus and Bos
indicus that are available in public databases, were used. Comparisons were made with
BLAST+ software, and alignment of sequences was performed using MEGA 7.0.26. software.
A total of 156 potential numts were found, of which 86 were confirmed. Although more
chromosomes of Bos indicus had matched sequences, the segment length itself was larger in
Bos taurus. The longest numt was 6393 bp long, while the shortest was 27 bp. The
correspondence between numt and mtDNA varies from 70% to 100%. The total length of
fragments in Bos taurus was 57189 bp, which is 3.5 times longer than the total length of the
mitogenome. The length of the Bos indicus’s segments fragment is 30609 pb, which is 1.9 times
longer than the total length of the mitogenome. In the mtDNA of Bos taurus, 5 full genes coding
for proteins were identified, namely 12s rRNA, COX1, COX2, COX3, ATP6, and they were
found in 9 numts. In total, 6 full genes: ND3, ND6, ATP6, ATP8, COX3, ND4L in 5 numts
were identified with mtDNA of Bos indicus. Most other numts encode the mt-tRNA genes.
Although protein-encoding genes have been discovered, further investigations are required to
verify the functionality of numts encoding mt-tRNA molecules. |