Telomeric profiles and telomerase activity in turkey satellite cell clones with different in vitro growth characteristics

The satellite cell population in postnatal skeletal muscle is heterogeneous because individual satellite cells isolated from a single muscle have differing abilities to proliferate under the same in vitro conditions. Telomeres are structures found at the ends of all eukaryotic chromosomes that are characterized by repetitive DNA sequences, and they are important in determining cellular proliferation potential. The relationship between satellite cell proliferative heterogeneity and telomeric DNA was examined by digesting genomic DNA from large-colony-forming and small-colony-forming turkey satellite cell clones with HinfI, separating the restriction fragments on an agarose gel, and hybridizing the gels with an oligonucleotide probe specific for telomeric DNA. Turkey satellite cells generated telomeric restriction fragments up to approximately 180 kB. The large-colony-forming satellite cell clones had a larger proportion (P<0.05) of total telomeric restriction fragments below 33 kB than the small-colony-forming satellite cell clones. However, telomerase expression was detected in cultures from large-colony-forming and small-colony-forming turkey satellite cells suggesting that the differences in telomeric restriction fragments may not be related to the differences in in vitro proliferative behavior and that telomerase may contribute to the high in vitro growth capacity of turkey satellite cells.