AUTHOR=Li Yan , Chen Xu , Wang Sha-Sha , Pan Bi-Ying , Wang Shi-Gui , Wang Su , Tang Bin 

TITLE=Evaluation of the Expression and Function of the TRE2-like and TRE2 Genes in Ecdysis of Harmonia axyridis

JOURNAL=Frontiers in Physiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2019.01371

DOI=10.3389/fphys.2019.01371

ISSN=1664-042X

ABSTRACT=<p><italic>Harmonia axyridis</italic> is an important predatory insect and widely used in biological control of agricultural and forestry pests. Trehalose is directly involved in the energy storage of the <italic>H. axyridis</italic> and in the oxidative function of various physiological activities thereby providing an energy source for its growth and development. The aim of this study was to explore the potential function of membrane-bound-like trehalase (<italic>TRE2-like</italic>) and membrane-bound trehalase (<italic>TRE2</italic>) genes in <italic>H. axyridis</italic> by RNAi. In addition, the activity of soluble and membrane-bound trehalase and the expression of genes related to trehalose and glycogen metabolism were determined in the larvae injected with ds<italic>TRE2-like</italic> or ds<italic>TRE2</italic>. The results showed that wing abnormality and mortality appeared in adults, as well as the activity of soluble trehalase and glycogen contents increased when interfering with <italic>TRE2-like</italic> gene. However, the activity of membrane-bound trehalase, trehalose and glucose contents in the larvae decreased. The expression of glycogen synthase (<italic>GS</italic>) and glycogen phosphorylase (<italic>GP</italic>) genes were decreased after RNAi in the ecdysis stage. The expression of chitin synthase gene A (<italic>CHSA</italic>), chitin synthase gene B (<italic>CHSB</italic>), and trehalose-6-phosphate synthase genes (<italic>TPS</italic>) were decreased significantly after RNAi, especially in the ecdysis stage. These results indicated that RNA interference is capable of knocking down gene expression of <italic>TRE2-like</italic> and <italic>TRE2</italic>, thereby disrupting trehalose metabolism which affects the chitin synthesis pathway in turn and also leads to developmental defects, such as wing deformities. This study could provide some theoretical guidance for the function of <italic>TRE2</italic> gene in other insects.</p>