Transcriptional Dynamics Underpinning Muscle Senescence in Manduca sexta

Abstract

Muscle aging is a complex dynamic process that adversely affects whole‐animal metabolism and physiology. The molecular regulation of aging muscle that impacts muscle function, performance, and metabolism remains largely unknown because such studies in model organisms are prohibitively time‐ and resource‐intensive. The hawk moth, Manduca sexta, offers a unique opportunity to identify the genes that coordinate the muscle aging process. With a complete lifespan of about ten days and being similar to vertebrate muscle systems, this non‐vertebrate animal model is ideal to conduct a molecular dissection of the regulatory genes underpinning the senescence process in muscles. Here, we characterize the genome‐wide transcriptional changes by profiling gene expression from a high‐resolution time course sampling of muscle tissue from middle age to advanced age moths. Following RNA‐Sequencing of the time course tissues, we not only report differentially expressed genes across the time and day intervals, but also construct gene regulatory networks to identify candidate genes that direct the aging process. This approach will allow us to uncover novel interactions and generate new hypotheses as to the fundamental processes surrounding muscle aging. We will discuss the genes coordinating muscle senescence which include, but are not limited to, the down‐regulation of ribosome biogenesis, upregulation of Z‐band‐associated‐proteins, and down‐regulation of nicotinic acetylcholine receptors. Our results provide an unprecedented view into the complex molecular regulatory events orchestrating muscle senescence. Support or Funding Information South Dakota Board of Regents Competitive Research Grant #A20‐0013‐001; Nolop Institute of Medical Biology Summer Research Scholarship