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Title: RNA editing controls meiotic drive by a Neurospora Spore killer
ABSTRACT NeurosporaSk-2is a complex meiotic drive element that is transmitted to offspring through sexual reproduction in a biased manner.Sk-2’s biased transmission mechanism involves spore killing, and recent evidence has demonstrated that spore killing is triggered by a gene calledrfk-1. However, a second gene,rsk, is also critically important for meiotic drive by spore killing because it allows offspring with anSk-2genotype to survive the toxic effects ofrfk-1. Here, we present evidence demonstrating thatrfk-1encodes two protein variants: a 102 amino acid RFK-1Aand a 130 amino acid RFK-1B, but only RFK-1Bis toxic. We also show that expression of RFK-1Brequires an early stop codon inrfk-1mRNA to undergo adenosine-to-inosine (A-to-I) mRNA editing. Finally, we demonstrate that RFK-1Bis toxic when expressed within vegetative tissue of Spore killer sensitive (SkS) strains, and that this vegetative toxicity can be overcome by co-expressingSk-2’s version of RSK. Overall, our results demonstrate thatSk-2uses RNA editing to control when its spore killer is produced, and that the primary killing and resistance functions ofSk-2can be conferred upon anSkSstrain by the transfer of only two genes.  more » « less
Award ID(s):
2005295
PAR ID:
10649487
Author(s) / Creator(s):
;
Publisher / Repository:
bioRxiv
Date Published:
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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