Cuticular Protein CP19a is Essential for the Response of Peach Aphid Myzus persicae

ABSTRACT

As an environmental stress, ultraviolet B (UV‐B) radiation can directly affect the growth, development and survival of insects. However, the role of cuticular protein in insect response to UV‐B stress remains unknown. The study investigates the critical role of the cuticular protein gene MpCP19a in Myzus persicae under UV‐B stress. Herein, the cuticular protein gene MpCP19a of M. persicae was cloned and identified. Sequence analysis revealed that it contains a typical ChtBD4 functional domain characteristic of the CPR protein family. MpCP19a was expressed in different developmental stages and tissues of M. persicae, with the highest expression in 2nd nymphs, as well as in the head and embryo, and the lowest in 1st nymphs and the gut. The expression level of MpCP19a in aphids was significantly up‐regulated upon UV‐B exposure. When MpCP19a was knocked down by RNAi, the survival rate of M. persicae decreased under UV‐B exposure, accompanied by a significant reduction in body size and the formation of brown pigmentation on the body surface. In contrast, under normal conditions (without UV‑B stress), knockdown of MpCP19a did not significantly affect survival rate, body size, or pigmentation compared with the dsGFP control and negative control group. These results indicate that MpCP19a plays an important role in regulating the growth and development of M. persicae and its molecular response to UV‐B stress, laying a foundation for developing key targets in insect control technologies.