Distinctive morphological and gene/protein expression signatures during myogenesis in novel cell lines from extraocular and hindlimb muscle

Abstract

Skeletal muscles are not created equal. The underutilized concept of muscle allotypes defines distinct muscle groups that differ in their intrinsic capacity to express novel traits when exposed to a facilitating extrinsic environment. Allotype-specific traits may have significance as determinants of the preferential involvement or sparing of muscle groups that is observed in a variety of neuromuscular diseases. Little is known, however, of the developmental mechanisms underlying the distinctive skeletal muscle allotypes. The lack of appropriate in vitro models, to dissociate the cell-autonomous and non-cell-autonomous mechanisms behind allotype diversity, has been a barrier to such studies. Here, we derived novel cell lines from the extraocular and hindlimb muscle allotypes and assessed their similarities and differences during early myogenesis using morphological and gene/protein expression profiling tools. Our data establish that there are fundamental differences in the transcriptional and cellular signaling pathways used by the two myoblast lineages. Taken together, these data show that myoblast lineage plays a significant role in the divergence of the distinctive muscle groups or allotypes.

Genomewide Analysis of Expression of Genes Located near miRNAs in Humans and Mice

“…As mouse data, GSE1049, GSE1052, GSE1301, GSE1745, GSE3234, GSE3351, and GSE26875 were used. (13)(14)(15)(16) Each dataset was obtained using Affymetrix Mouse Expression 430B Array.…”

Craniofacial Muscle Development

“…In contrast, Isl1 lineage solely marks PA-derived head muscles and their associated satellite cells (Harel et al, 2009). Differences between satellite cell populations are retained in their myoblast progeny and into adulthood (Ono, Boldrin, Knopp, Morgan, & Zammit, 2010;Porter et al, 2006). Interestingly, myogenic differentiation of head muscles is delayed compared to myogenesis derived from the somites (Hacker & Guthrie, 1998;Noden et al, 1999).…”

Perimysial Fibroblasts of Extraocular Muscle, as Unique as the Muscle Fibers

“…Stock cell lines of extraocular muscle (CL-EOM) and limb muscle (CL-LM), which have previously been described and extensively verified as pure populations of myoblasts, 16 were used for all co-culture studies. For proliferation, myoblasts were seeded on 0.5% gelatincoated plates with myoblast growth medium (F10C: F10 plus 1% penicillin-streptomycin, 1 mM L-glutamine, 1.2 mM CaCl 2 , 15% horse serum, and 6 ng/mL fibroblast growth factor [FGF]).…”

“…16 We co-cultured EOM-and LM-Fibro with the CL-EOM and CL-LM to assess the impact of fibroblasts on mature myotube formation, as determined by the percentage of myotubes with greater than three nuclei. Co-culture of CL-EOM or -LM with EOMor LM-Fibro led to a greater percentage of myotubes with more than three nuclei for longer times in culture than CL-EOM or -LM plated on gelatin (data not shown).…”