Photosynthesis-related proteins of cup-shaped galls in Litsea acuminata leaves

Insect-induced galls are an atypical growth and differentiation form of plant tissue. The objective of this research was to study the expression of photosynthesis-associated proteins in Cecidomyiidae galls derived from the leaves of Litsea acuminata using a Western blot analysis of antibodies against light-harvesting complex (LHC) proteins isolated from non-galled and galled leaves and gall tissues. These LHC proteins involved in RC-1a, RC-1b, LHCb4, LHCb5, CP47, and CP-1a showed different responses in galls and leaves and exhibited a remarkable potential modulation role in regulating gall development. All photosynthetic proteins were repressed in gall tissues, indicating that light reaction functioning was significantly repressed. Compared to non-galled and galled leaves, galls demonstrated significantly lower chlorophyll (Chl) content and photosystem II maximum quantum efficiency (F_v/F_m) values, suggesting that insect infestations reduced photosynthetic efficiency. In addition, there were significant and positive correlations between LHCb5, CP-1a, and CP47 vs. Fv/Fm values and Chl content in galls and leaves, indicating that gall infections induced physiological changes, and therefore, that the Fv/Fm value could be utilized as a tool to easily and quickly study the eco-physiology of galls.