Department of Zoology, Indira Gandhi National Tribal University, Amarkantak 484887, India.
Department of Genetics, M. D. University, Rohtak 124001, India.
Comp Biochem Physiol A Mol Integr Physiol. 2022 Sep;271:111258. doi: 10.1016/j.cbpa.2022.111258. Epub 2022 Jun 12.
Seasonally polyphenic types have been documented in many Drosophilids, which differ significantly during thermal stress. Although Drosophila simulans is a sibling species to Drosophila melanogaster, both thrive in the temperate and tropical climates, but various climatic factors are expected to impact their distribution and abundance. As a result, D. simulans may use phenotypic plasticity to adapt to colder and drier circumstances in temperate zones, although such studies are less known. In the present study, our main aim was to find a link between adaptive plasticity and thermal tolerance in D. simulans. We characterized two morphs in D. simulans flies based on the abdominal melanization collected from the same locality and season, as this trait is highly associated with the larval developmental conditions. Our results suggested that flies reared from dark and light morph showed significant differences in the basal level of proline, carbohydrates (trehalose, glycogen), and lipids (cuticular lipids and total body lipids) within simulated seasons and morph lineages in D. simulans flies. We further showed that D. simulans reared from dark morph are better adapted to cold conditions, whereas light flies are more adapted to warm conditions. The flies, both from light and dark morph lineages, when reared at 15 °C, showed an increase in the level of total body lipids after acclimation at 0 °C but a decrease in the level of proline and carbohydrates (trehalose, glycogen). Heat acclimation increases glycogen levels in the flies from light morph lineage while decreases trehalose and proline.
许多果蝇中都有季节性多态性类型的记录，这些类型在热应激时会有显著差异。虽然拟暗果蝇是黑腹果蝇的姊妹种，但它们都在温带和热带气候中繁衍生息，但各种气候因素预计会影响它们的分布和丰度。因此，拟暗果蝇可能会利用表型可塑性来适应温带地区较冷和较干燥的环境，尽管此类研究较少。在本研究中，我们的主要目的是在拟暗果蝇中找到适应性可塑性和热耐受性之间的联系。我们根据从同一地点和季节收集的腹部黑化特征，对拟暗果蝇中的两种形态进行了表征，因为这种特征与幼虫发育条件高度相关。我们的结果表明，在模拟季节和形态谱系中，从深色和浅色形态中饲养的果蝇在脯氨酸、碳水化合物（海藻糖、糖原）和脂质（表皮脂质和总体脂质）的基础水平上存在显著差异。我们进一步表明，从深色形态中饲养的拟暗果蝇更适应寒冷条件，而浅色果蝇更适应温暖条件。无论是深色还是浅色形态谱系的果蝇，在 15°C 下饲养时，在 0°C 下适应后，总体脂质水平会增加，但脯氨酸和碳水化合物（海藻糖、糖原）水平会降低。热适应会增加浅色形态谱系中果蝇的糖原水平，同时降低海藻糖和脯氨酸水平。
