Multiple losses of aKRAB from PRDM9 coincide with a teleost-specific intron size distribution.

ABSTRACT:

Background

Primary transcripts are largely comprised of intronic sequences that are excised and discarded shortly after synthesis. In vertebrates, the shape of the intron size distribution is largely constant; however, most teleost fish have a diverged log-bimodal 'teleost distribution' (TD) that is seen only in teleosts. How the TD evolved and to what extent this was affected by adaptative or non-adaptive mechanisms is unknown.

Results

Here, we show that the TD has evolved independently at least six times and that its appearance is linked to the loss of the aKRAB domain from PRDM9. We determined intron size distributions and identified PRDM9 orthologues from annotated genomes in addition to scanning 1193 teleost assemblies for the aKRAB domain. We show that a diverged form

SUBMITTER: Zinner AC 

PROVIDER: S-EPMC11600626 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature