Meeting Abstract

P3.6  Monday, Jan. 6 15:30  Does cis-regulatory variation in avpr1a shape sexual fidelity through spatial memory? WALLACE, G*; DEHGHANI, Z; OKHOVAT, M; BERRIO ESCOBAR, A; PHELPS, S; Univ. of Texas, Austin GerardnWallace@gmail.com

Prairie voles are socially monogamous, but many young are sired outside the pair. Males who obtain extra-pair fertilizations (EPFs) intrude more often into neighboring territories and have low expression of vasopressin 1a receptor (V1aR) in retrosplenial cortex (RSC), a region important in spatial memory. We hypothesize that males lacking RSC-V1aR have poorer memory for locations of aversive interaction, and that this leads to both territorial intrusion and EPFs. RSC-V1aR is predicted by 3 tightly linked SNPs in the vicinity of the V1aR gene (avpr1a). To test this association more fully, heterozygous parents (HET) were crossed to obtain HI, LO and HET offspring. We found both breeding pair (P<0.001) and offspring genotype (P<0.02) were significant predictors of RSC-V1aR abundance. The socio-spatial memory of HI and LO males was assessed using a Barnes maze modified to simulate spatial memory demands during territorial escape. On the first trial of each day, a pair-bonded resident male was tethered in the center of the arena; on subsequent trials subjects were tested with no male present. Subjects readily learned escape routes using spatial cues, with fewer errors on trial 8 than on trial 1 (P<0.05), and fewer on trial 16 than trial 8 (P<0.01). We did not observe an effect of genotype (P>0.05) on error rates. To our surprise, pair-bonded stimulus animals were not aggressive, thus the spatial memory demands may not accurately model memory for punitive encounters in the field. We are currently examining RSC-V1aR to determine whether neuronal phenotype is a stronger predictor of memory in this task than genotype. Overall, we expect these experiments to clarify the role of genetics and neuronal phenotype on memory and sexual fidelity in the field.