Mating time characterization of Anastrepha fraterculus and Anastrepha obliqua (Diptera, Tephritidae) and the expression of the cycle gene

• Grant number: 14/08090-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2014
• End date: December 31, 2014
• Field of knowledge: Biological Sciences - Genetics
• Principal Investigator: Reinaldo Otávio Alvarenga Alves de Brito
• Grantee: Lucas Packer Arthur
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Circadian rhythms are daily cycles of physiological and behavioral processes based on a period of approximately 24 hours. These processes are regulated by the biological clock that is responsible for synchronizing the living organisms and their functions with the environment they live. The circadian rhythm of the fly model Drosophila melanogaster can be molecularly explained by negative feedback loops involving genes such as cycle (cyc), Clock (Clk), period (per) and timeless (tim). The heterodimer formed by CYC and CLK proteins acts as a transcription factor in the main positive regulatory loop of the clock mechanism. The expression of cyc gene is cyclical in all insects studied to date, but D. melanogaster is an exception. To our knowledge, informations on clock genes of the fruit flies Anastrepha fraterculus and Anastrepha obliqua have not been published yet. In addition, the expression of these genes are also unknown, including the gene cyc. Therefore, this study aims to characterize and investigate the expression of cyc in these two species. To do so, the initial step of molecular studies were taken by the identification of transcripts in cDNA libraries generated from strategies of next-generation sequencing (Next Gen). A "consensus" sequence for each species were assembled and from them, primers were already designed for both, conventional PCR and real-time PCR. Thus, we will characterize the complete sequence of cyc. Fragments generated by PCR and sequenced by Sanger will confirm the nucleotide sequences. The expression pattern of the gene will be established in different physiological stages using males and females virgin and post copulated flies. With these studies, we will investigate whether the expression is cyclic or not. Considering that the daily pattern of copulation is unknown in these two flies, another proposed objective is to investigate the standard time of copulation in both species. This will facilitate the use of individuals at specific times of the day for the studies of gene expressions. For this, observations of couples will be conducted for 24 consecutive hours. Taken together, the results here obtained will contribute to understand the biological clock of A. fraterculus and A. obliqua, two serious pests of Brazilian fruitculture. (AU)