Allele-biased expression during heat stress in copepods

Adaptive divergence between isolated populations can result from evolution at protein sequences and/or at regulatory sequences that alter gene expression. Our understanding of the latter mechanism is relatively poor, especially in natural systems. This project aims to quantify evolutionary divergence in gene transcription regulation between two population of the intertidal copepods Tigriopus californicus. Populations from San Diego, California (SD), are substantially more tolerant to heat stress than those from Strawberry Hill, Oregon (SH). By quantifying gene expression in first-generation (F1) hybrids between SD and SH during experimental high-temperature stress, we are determining the relative importance of cis- versus trans-regulatory mutations.