Expression Levels of Heat-Shock Proteins in and Foragers in the Desert Climate of Saudi Arabia.

is the indigenous honeybee of the Arabian Peninsula. It is highly adapted to extreme temperatures exceeding 40 °C, yet important molecular aspects of its adaptation are not well documented. In this study we quantify relative expression levels of small- and large-molecular-weight heat-shock proteins (, , , , and (mRNAs)) in the thermos-tolerant and thermosusceptible forager honeybee subspecies under desert (Riyadh) and semi-arid (Baha) summer conditions. The results showed significant day-long higher expression levels of mRNAs in compared to under the same conditions. In Baha, the expression levels were very modest in both subspecies compared those in Riyadh though the expression levels were higher . The results also revealed a significant interaction between subspecies, which indicated milder stress conditions in Baha. In conclusion, the higher expression levels of , , , and mRNAs in are key elements in the adaptive nature of to local conditions that enhance its survival and fitness in high summer temperatures.