Akademik Veri Yönetim Sistemi
AKDENİZ ZİRVESİ 3. ULUSLARARASI UYGULAMALI BİLİMLER KONGRESİ, Girne, Kıbrıs (Kktc), 17 - 18 Ekim 2020, ss.7-8
ABSTRACT
Tropical theileriosis caused by the tick transmitted
protozoa parasite Theileria annulata
is an economically important disease of cattle in many developing countries.
The genetic and antigenic diversity within and between field parasite
populations is an important epidemiological parameter that needs to be
investigated and quantified for the development and deployment of novel control
strategies. The effective role of recombination for generating genetic and
antigenic diversity in natural parasite populations has been proposed. These
recombined and genetically diverse parasite populations can give rise to new
risk factors, such as drug resistance, reduced vaccine protection, occurrence
of highly pathogenic isolates. Previous data indicated that genetic and
antigenic diversity in T. annulata
populations vary not only between different geographical regions but also
within a single host and this polymorphism is presumed to be due to the high
level of genetic exchange occurring in parasite populations. The occurrence of
a sexual cycle has been confirmed in a closely related orthologue parasite, T. parva, however in T. annulata, an evidence for the
occurrence of mating has came from population genetic studies and no
experimental data is available yet regarding to the role of recombination after
transmission of T. annulata to ticks.
The completed genome sequence of T.
annulata provided an opportunity to develop genetic markers for population
genetic studies and also enabled the identification of new antigens. In this
study, a panel of 23 micro and minisatellite markers were used to identify,
characterise and analyse two different clonal and nonclonal T.annulata isolates after recombination.
We have measured the frequency of recombination in T. annulata isolates for each of four chromosomes. We have also
investigated effect of recombination on antigenic diversity. The analysis using
polymorphic markers demonstrated the existence of genetic exchange between T. annulata isolates and this evident
recombination was experimentally shown for the first time. The highest level of
recombination was found to be located on the forth chromosome. However, there
was no correlation between recombination rate and chromosomal length. It should
be pointed out that none of the recombined populations detected in the present
study showed a detectable level of antigenic diversity. This study was
financially supported by TUBITAK-111O718.
Key
Words: Population
Genetics, Sexual Recombination, Theileria
annulata