Data from: Genetic variation in bitter taste receptor genes influences the foraging behavior of plateau zokor (Eospalax baileyi)

The ability to detect bitter tastes is important for animals; it can help them to avoid ingesting harmful substances. Bitter taste perception is mainly mediated by bitter taste receptor proteins, which are encoded by members of the Tas2r gene family and vary with the dietary preference of a specific species. Although individuals with different genotypes differ in bitterness recognition capability, little is known about the relationship between genetic variation and food selection tendencies at the intraspecific level. In this study, we examined the relationship between genotypes and diet in plateau zokor (Eospalax baileyi), a subterranean rodent endemic to the Qinghai-Tibet Plateau that caches food for the winter. We assayed the composition and taste profile of each plant contained in temporary caches and vicinity quadrats, which were representative of selected and available food, respectively. Bitter plant selection indices (Ebitter) were estimated. We also sequenced 26 candidate Tas2r genes from zokors and determined their relationships with the Ebitter of their caches. We identified four key results: (1) zokors varied considerably in both bitter food preference and Tas2r sequences; (2) five genes (zTas2r115, zTas2r119, zTas2r126, zTas2r134, and zTas2r136) exhibited allelic variation that was significantly associated with Ebitter; (3) synonymous SNPs, nonsynonymous SNPs, and pseudogenization are involved in the genotype–phenotype relationship; (4) the minor genotypes of zTas2r115, zTas2r134, and zTas2r136 and the major genotypes of zTas2r119 and zTas2r126 cached more bitter plants. Our results link Tas2r variation with food selection behavior at the population level for the first time.味觉识别苦味的能力对动物而言至关重要，可帮助其规避摄入有害物质。苦味感知主要由苦味受体蛋白介导，这类蛋白由Tas2r基因家族（Tas2r gene family）成员编码，且随特定物种的食性偏好发生变异。尽管不同基因型个体的苦味识别能力存在差异，但目前学界对种内水平上遗传变异与食物选择倾向之间的关联仍知之甚少。本研究以青藏高原特有、冬季会储备食物的地下啮齿类——高原鼢鼠（Eospalax baileyi）为对象，探究其基因型与饮食之间的关联。我们分别测定了代表其选择食物的临时储粮点，以及代表可获得食物的周边样方内每种植物的组成与味觉特征，并估算了苦味植物选择指数（Ebitter）。此外，我们还对鼢鼠体内的26个候选Tas2r基因进行了测序，并明确了这些基因与其储粮的Ebitter值之间的关联。本研究得到四项核心结论：（1）高原鼢鼠的苦味食物偏好与Tas2r序列均存在显著个体差异；（2）5个基因（zTas2r115、zTas2r119、zTas2r126、zTas2r134与zTas2r136）的等位基因变异与Ebitter值显著相关；（3）同义单核苷酸多态性位点、非同义单核苷酸多态性位点以及假基因化均参与了基因型-表型关联的形成；（4）zTas2r115、zTas2r134与zTas2r136的次要基因型，以及zTas2r119与zTas2r126的主要基因型个体，会储存更多苦味植物。本研究首次在种群水平上建立了Tas2r基因变异与食物选择行为之间的关联。