Control of yeast retrotransposons mediated through nucleoporin evolution

Area of Science:

• * Molecular Biology
• * Evolutionary Genetics
• * Cell Biology

Background:

• * Yeasts host genetic parasites, including Ty retrotransposons, which require nuclear access.
• * The evolutionary pressures shaping host genes that regulate parasite coexistence are understudied.
• * The nuclear pore complex (NPC) controls nuclear transport and is crucial for host-parasite interactions.

Purpose of the Study:

• * To investigate the evolutionary trajectory of yeast nuclear pore complex genes.
• * To determine how natural selection on NPC genes affects the mobility of Ty retrotransposons.
• * To assess if evolutionary changes in NPC genes impact essential housekeeping functions.

Main Methods:

• * Comparative genomics to identify genes under natural selection in Saccharomyces species.
• * Gene replacement experiments using orthologs of NUP84 and NUP82 from different Saccharomyces species in S. cerevisiae.
• * Assessing Ty retrotransposon mobility and NUP84/NUP82 housekeeping functions in modified yeast strains.

Main Results:

• * Several yeast nuclear pore complex genes show signatures of natural selection for protein sequence changes.
• * Replacing S. cerevisiae NUP84 or NUP82 genes with orthologs from other Saccharomyces species altered Ty1 and Ty3 retrotransposon mobility.
• * Essential housekeeping functions of NUP84 and NUP82 remained equivalent across tested species.

Conclusions:

• * Evolutionary adaptations in the nuclear pore complex can modulate the replication of genetic parasites.
• * Essential housekeeping proteins, like NPC components, can evolve under selection related to parasitic interactions.
• * The study demonstrates a mechanism by which host-parasite dynamics shape essential cellular machinery without compromising vital functions.