تحلیل مولکولی و فیلوژنتیکی ژن انسولین و گیرنده آن در سن گندم (Eurygaster integriceps)

The Sunn pest , Eurygaster integriceps Puton (Hemiptera: Scutelleridae), is one of the most important agricultural pests in Iran and neighboring countries. It attacks wheat and barley, feeding on leaves, stems, and grains, causing both quantitative and qualitative damage. This univoltine pest has two main life stages: the active period and diapause. The primary causes of diapause are low temperatures in autumn and winter, as well as food shortages in wheat and barley fields. In summer, this pest also enters diapause and migrates to mountainous areas with lower temperatures when the heat increases. However, the precise molecular and genetic mechanisms of diapause are not yet fully understood, and studying the genes that may play a role in diapause regulation can help to better understand this stage. Studies show that insulin and its receptors play important roles in regulating diapause, metabolism, growth, reproduction, and aging in insects. Insulin-like peptides (ILPs) in insects act as mitogenic growth factors and help in tissue growth and development. Findings suggest that the insulin signaling pathway, including the insulin receptor, is likely involved in regulating diapause in the Sunn pest as well. This study focuses on the phylogenetic analysis of the insulin gene and its receptor. For this purpose, RNA was isolated from the Whole body of an adult insect using Tri-Reagent (Sigma) according to its protocol. To ensure the quality and quantity of the extracted RNA, gel electrophoresis and a Nanodrop device were used, respectively. Single-stranded cDNA was synthesized using the AddScript cDNA Synthesis Kit (Addbio) according to the manufacturer's instructions. The prepared cDNA was used as a template strand in the polymerase chain reaction (PCR). Specific primers for amplifying these genes were designed using Oligo7 software. PCR was performed using a thermocycler, and the final product was used for sequencing. Using Sanger sequencing, the sequences of the desired genes were identified. The relationship of this gene in this pest with other insects in the Hemiptera order was examined. Accordingly, the results of the phylogenetic tree showed that Halyomorpha halys has the closest evolutionary molecular relationship with E. integriceps, and other insects in the phylogenetic tree were less closely related.