Telomeric profiles and telomerase activity in turkey satellite cell cloneswith 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 diff ering abilities to proliferate under the same in vitro conditions. Telomere s are structures found at the ends of all eukaryotic chromosomes that are c haracterized by repetitive DNA sequences, and they are important in determi ning cellular proliferation potential. The relationship between satellite c ell proliferative heterogeneity and telomeric DNA was examined by digesting genomic DNA from large-colony-forming and small-colony-forming turkey sate llite cell clones with HinfI, separating the restriction fragments on an ag arose gel, and hybridizing the gels with an oligonucleotide probe specific for telomeric DNA. Turkey satellite cells generated telomeric restriction f ragments up to approximately 180 kB. The large-colony-forming satellite cel l 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-f orming and small-colony-forming turkey satellite cells suggesting that the differences in telomeric restriction fragments may not be related to the di fferences in in vitro proliferative behavior and that telomerase may contri bute to the high in vitro growth capacity of turkey satellite cells. (C) 20 00 Elsevier Science B.V. All rights reserved.