| Definition: |
Tyrosine Kinase (YR) retrotransposons are a subclass of non-LTR retrotransposons. These YR-encoding elements consist of central gag, pol and tyrosine recombinase (YR) open reading frames (ORFs) flanked with terminal repeat. The pol ORF includes a reverse transcriptase (RT), a RNase H (RH) and, in case of DIRS, a domain similar to bacterial and phage DNA N-6-adenine-methyltransferase (MT). Compared to the retroviral pol (LTR retrotransposons, non-LTR retrotransposons and Penelope elements), both aspartic protease and DDE integrase are absent from YR retrotransposons. YR retrotransposons have inverted terminal repeats (ITRs). |