Pluto Bioinformatics

GSE139209: The neuromuscular junction is a focal point of mTORC1 signaling in sarcopenia [NMJ data set].

Bulk RNA sequencing

Purpose: To investigate whether our signatures of mTORC1-driven sarcopenia originate from cells residing at the neuromuscular junction (NMJ), we followed laser-capture microdissection with RNA-seq from adult and sarcopenic tibialis anterior (TA) muscles.; Methods: TA muscles were incubated in solution containing fluorescently-labeled bungarotoxin, which binds to post-synaptic AChRs and thereby marks NMJ regions. Approximately 300 synaptic regions (NMJ) and a comparable number of extra-synaptic (xNMJ) regions were collected from 30M thick sections using laser-capture microdissection (LCM) and processed for RNA-seq.; Results: As compared to xNMJ regions, NMJ regions were highly enriched for genes known to be specifically expressed at the NMJ. The analysis demonstrated that genes associated with sarcopenia are significantly enriched at the NMJ in young (10 months) and old (30 months) mice. Furthermore, the age-related reduction in expression of genes associated with extracellular matrix (ECM) remodelling was particularly prominent in NMJ regions but not in xNMJ regions.; Conclusions: Diminished expression of ECM genes at the NMJ may impact the stability of the NMJ and its ability to remodel following common age-related remodelling events such as muscle fiber degeneration/regeneration and motor unit loss. SOURCE: Anastasiya Boersch (anastasiya.boersch@gmail.com) - University of Basel