Restriction Factor Control of Ty1 Family LTR-Retrotransposons in Saccharomyces cerevisiae
Year: 2026
Type: review
Abstract: contains several active retrotransposon families but maintains a remarkably compact genome, all without many of the transposon control systems used in mammals. Here, we review restriction factor control of the yeast Ty1 family of LTR-retrotransposons. Several decades of study have identified a novel mechanism that provides highly specific restriction of Ty1 using transposon-derived sequences. Recent work combining structural, biophysical, biochemical, and genetic techniques has revealed a detailed mechanism of this restriction and the determinants of specificity. Interestingly, two Ty1 subfamilies each converged on the same restriction mechanism despite following separate evolutionary histories. The protein p22/p18 is a self-encoded restriction factor that targets Ty1c and is produced from an internally initiated mRNA. Drt2 is a restriction factor that targets Ty1' and is produced from a transposon fragment endogenized by the host genome. Both interfere with the assembly of transposon virus-like particles using a shared dimerization surface, but subtle sequence divergence in this interface directs each restriction factor against its specific Ty1 subfamily. This work presents a framework to identify novel transposon control systems in other organisms.
Source: Viruses
DOI: 10.3390/v18101154
Institution: Hope College
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,137
OpenAlex ID: W7222944517