Study of the microRNAs involved in catabolic and anabolic pathways in red and white skeletal muscle of pacu (Piaractus mesopotamicus) during fasting and re-feeding

Abstract

The skeletal muscle in fish comprising the most part of body mass and their growth occurs by hypertrophy and/or hyperplasia of the muscle fibers, processes that vary with species, stage of development, and nutritional status. The development, growth, and the maintenance of muscle phenotype involve the activation or inhibition of signaling pathways that are responsible for controlling the anabolic and catabolic activities pathways in muscle tissue. Recently, small non-coding RNAs (microRNAS) have been described as modulators of these pathways, influencing levels of protein synthesis and degradation. Based on this, studies that seek to elucidate the interaction between microRNAs and their targets, and their role in muscular mass control are important for a better understanding about the role of the microRNA in this process and in conditions that occurs a homeostasis change between anabolic and catabolic states, as in situations of food restriction and re-feeding conditions. The aim of this study is to evaluate the gene expression of microRNAs (miR-1, miR-23a, miR-206 e miR-199b) and their targets (IGF-1, PGC-1±, MAFbx e mTOR) in red and white muscle of juvenile of pacu (150g) submitted a period of fasting (10 days) and re-feeding (03 days). The microRNA expression will be perform by Real Time Polymerase Chain Reaction after Reverse Transcription (RT-qPCR) in the groups G-10 (control group), T0 (zero days of fasting) and G5 (60 hours of re-feeding). The data will be subjected to appropriate statistical analysis after the completion of tests of normality and homoscedasticity.