Fig. 4
From: The genetic basis of a social polymorphism in halictid bees
Functional effects of regulatory SNPs in the syx1a locus. a Schematic of syx1a. Arrows denote locations of the seven SNPs associated with social behavior in L. albipes. Arrow colors illustrate FST between social forms at each SNP. Two SNPs, labeled SNP 1 and 2 (red), have the highest FST estimates, and are in strong LD with each other (r2 = 0.803), compared with the mean pairwise value among all seven SNPs (r2 = 0.18). b Quantitative PCR identified differences in syx1a brain gene expression between social forms. Expression values are plotted as the fold change of normalized syx1a expression levels. Social individuals (n = 4) have significantly higher levels of syx1a brain gene expression than solitary individuals (n = 5; t-test, t = −6.32, p = 0.0004). c Luciferase reporter assays test if candidate SNPs in the regulatory regions of syx1a affect enhancer activity (n = 5 replicates per group). Both tested regions show enhancer activity relative to control (Tukey’s honestly significant difference (HSD) post-hoc test, p < 0.05). There is no significant difference between social and solitary alleles of SNP 1 (Tukey’s HSD, p = 0.1773), but the social allele of SNP 2 drives ~1.5 times higher reporter expression than does the solitary allele (Tukey’s HSD, p < 0.0001), consistent with the qPCR assay (b)
