Abstract:

Olfaction plays an important role in survival and reproduction of insects. Many proteins from olfactory sensory neurons participate in the olfactory recognition process,including odorant binding protein (OBP),odorant receptor (OR),odorant degrading enzyme (ODE),chemosensory protein (CSP),and sensory neuron membrane protein (SNMP). As an important protein,OR mediates the specific combination of odour molecules and olfactory neurons,which is an important basis for insects to perform olfactory functions. Because the OR structure of insects is different from that of vertebrates,it cannot be obtained by homologous cloning for long time. Thus,ORs discovery of insects has taken a long time. ORs can be divided into two categories. The first category is the functional receptors to recognize various odour molecules,the second one is the receptor without odour molecules recognition function,which co-expresses with other functional receptors to perform olfactory functions together. Researches on OR mainly focus on its identification and functional exploration. At present,there are three expression systems in vitro commonly used in the functional analyses of OR,including the Xenopus oocyte expression system,the heterologous cell expression system,and the Drosophila empty neuron expression system. As for in vivo methods for researching the gene functions,RNAi (RNA interference,RNAi) and Crispr/Cas9 (clustered regularly interspaced short palindromic repeats/Crispr-associated sequence) systems have also been used to explore the OR's function in some insects. Researches on the mechanism of insects OR mainly focus on some model insects. Although forest insects are important insects,their OR research started late. At present,researches about OR in forest insect are mainly gene identification,and only few work is on gene function. The research on the olfactory receptor mechanism provides a good direction for pest control,and it is worth to further strengthen researches about the mechanisms and pest control methods based on olfactory regulation.

Key words: odorant receptors, gene function, research techniques, forest insects, forest pest control