Borysenko L. Distribution and expression of endogenous retroviruses in the avian genome

The dissertation is devoted to the problem of specificity of localization and expression of avian endogenous retroviruses in the host genome. Distribution of seven groups of chicken endogenous retroviruses (ALV-related ev loci, HERV-I-related proviruses, EAV-HP, EAV-0, E-33, E-51, ART-CH) was studied according to the composition (long-range variation of GC-content) of the host genome. It has been established that the localization of retroviruses was isopycnic which means that GC-content of provirus matches GC-level of host genome region where integration took place. Some proviruses of E-33/E-51 group and provirus EAV-HP have additional peaks in non-isopycnic regions. Investigation of expression provided a tissue-specific patterns that could change the picture of proviral distribution due to reintegration. It has been shown that the chicken genome contains not only ALV-related proviruses but also HERV-I (human endogenous retrovirus type I)-related.