Data from: Adaptive reduction of male gamete number in the selfing plant Arabidopsis thaliana

The number of male gametes is critical for reproductive success and varies
between and within species. The evolutionary reduction of the number of
pollen grains encompassing the male gametes is widespread in selfing
plants. Here, we employ genome-wide association study (GWAS) to identify
underlying loci and to assess the molecular signatures of selection on
pollen number-associated loci in the predominantly selfing plant
Arabidopsis thaliana. Regions of strong association with pollen number are
enriched for signatures of selection, indicating polygenic selection. We
isolate the gene REDUCED POLLEN NUMBER1 (RDP1) at the locus with the
strongest association. We validate its effect using a quantitative
complementation test with CRISPR/Cas9-generated null mutants in
nonstandard wild accessions. In contrast to pleiotropic null mutants, only
pollen numbers are significantly affected by natural allelic variants.
These data support theoretical predictions that reduced investment in male
gametes is advantageous in predominantly selfing species.