| Abstract Detail
Reproductive Processes Harkness, Alexander [1], Brandvain, Yaniv [2], Goldberg, Emma [1]. Self-incompatibility haplotypes can diversify through sequential mutation and gene conversion. The origin of novel complex regulatory mechanisms is a central problem in evolutionary biology. The RNase-based system of self-pollen rejection in the Solanacese is a prime example of this problem. In this case, an S-haplotype consists of a poison RNase expressed in the style tightly linked to multiple SLF paralogs which act as antidotes expressed in pollen. The SLF that detoxifies a given RNase is not found on that haplotype and thus self pollen is rejected, while pollen from other S-haplotypes can be accepted. Clearly, there is no benefit to a stylar poison without an antidote, and there is similarly no benefit to an SLF antidote without a toxin. How then can a new incompatibility allele spread? Here we develop a population genetic model of the evolution of a novel S-haplotype. We show that a novel RNase poison is initially favored because it reduces the fitness of haplotypes lacking the antidote to it, and a new equilibrium of RNases is achieved. We then show the conditions allowing the SLF variant that detoxifies this RNase to spread through the population by gene conversion before S-haplotypes lacking this antidote are lost. Our results show that a parsimonious model including only gene conversion and known incompatibility relations is sufficient to explain the possibility of diversification of S-locus haplotypes, though additional factors probably determine the rate of RNase diversification in nature. Log in to add this item to your schedule
1 - University of Minnesota, Ecology, Evolution, and Behavior, 1479 Gortner Ave, 140 Gortner Lab, St. Paul, MN, 55108, United States 2 - University of Minnesota, Plant and Microbial Biology, 1479 Gortner Ave, 140 Gortner Lab, St. Paul, MN, 55108, United States
Keywords: Self-incompatibility Breeding system Solanaceae.
Presentation Type: Poster Session: P, Reproductive Processes Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center Date: Monday, July 23rd, 2018 Time: 5:30 PM This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm. Number: PRP009 Abstract ID:435 Candidate for Awards:None |