Dataset Information

Gene expression analysis in Tibialis anterior (TA) muscle upon titration of myonuclear numbers

ABSTRACT: Skeletal muscle myofibers accrue hundreds of nuclei during post-natal development via fusion with activated satellite cells (myoblasts), which is absolutely reliant on expression of the muscle fusogen myomaker (Mymk) in the myoblasts. Using an inducible genetic approach to render myoblasts non-fusogenic (by tamoxifen-inducible Pax7-CreER mediated recombination of the Mymk gene exclusively in satellite cells), we blocked myonuclear accrual at different time-points of post-natal development and thereby titrated the number of nuclei in resultant mutant myofibers. These Microarray assays were carried out on age day 28 (P28) using total RNA isolated from control and mutant muscle to determine changes in transcriptional profiles of these muscles to (a) assess effects of myonuclear titration, and (b) identify adaptive mechanisms elicited in mutant muscles in response to myonuclear deficiency. We used microarrays to generate information about transcriptional profiles in muscles with varying levels of myonuclear deficiencies.

ORGANISM(S): Mus musculus

PROVIDER: GSE141296 | GEO | 2020/08/25

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:MicroRNAs (miRNAs) are important in the regulation of many biological processes including muscle development. However, little is known regarding miRNA regulation of muscle regeneration. In mature murine tibialis anterior muscle following injury, 298 miRNAs were significantly changed during the time course of muscle regeneration including 86 that were altered greater than 10-fold as compared to uninjured muscle. Temporal miRNA expression patterns were identified and included inflammation-related miRNAs (miR-223 and -147) that increased immediately after injury; this pattern contrasted to that of mature muscle-specific miRNAs (miR-1, -133a and -499) that were abruptly decreased following injury and then up-regulated in later regenerative events. Another cluster of miRNAs were transiently increased in the early days of muscle regeneration. This included miR-351, a miRNA that was also transiently expressed during myogenic progenitor cell (MPC) differentiation in vitro. Based on computational predictions, further studies demonstrated that E2f3 was a target of miR-351 in myoblasts. Moreover, knockdown of miR-351 expression inhibited MPC proliferation and promoted apoptosis during MPC differentiation, whereas miR-351 overexpression protected MPC from apoptosis during differentiation. Collectively, these observations suggest that miR-351 is involved in both the maintenance of MPC proliferation and the transition of MPC into differentiated myotubes. Thus, a novel, time-dependent sequence of molecular events during skeletal muscle regeneration has been identified, i.e., miR-351 inhibits E2f3 expression, a key regulator of cell cycle progression and proliferation, and promotes MPC proliferation and protects early differentiating MPC from apoptosis, important events in the hostile tissue environment after acute muscle injury. Skeletal muscles are damaged and repaired repeatedly throughout life. Muscle regeneration maintains locomotor function during aging and delays the appearance of clinical symptoms in neuromuscular diseases, such as Duchenne muscular dystrophy. The capacity for skeletal muscle growth and regeneration is conferred by satellite cells located between the basal lamina and the sarcolemma of mature myofibers. Upon injury, satellite cells reenter the cell cycle, proliferate, and then exit the cell cycle either to renew the quiescent satellite cell pool or to differentiate into mature myofibers. Despite recent advances, genes involved in these processes are still largely unknown. Understanding the molecular mechanisms that regulate satellite cell activities could promote development of novel countermeasures to enhance muscle regeneration that is compromised by diseases or aging. Using a muscle injury mouse model, we profiled miRNA expression during muscle regeneration.

Dataset Information

Gene expression analysis in Tibialis anterior (TA) muscle upon titration of myonuclear numbers

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure