Extraordinarily rapid proliferation of cultured muscle satellite cells from migratory birds

<p>Migratory birds experience bouts of muscle growth and depletion as they prepare for, and undertake prolonged flight. Our studies of migratory bird muscle physiology <i>in vitro</i> led to the discovery that sanderling (<i>Calidris alba</i>) muscle satellite cells proliferate more rapidly than other normal cell lines. Here we determined the proliferation rate of muscle satellite cells isolated from five migratory species (sanderling; ruff, <i>Calidris pugnax</i>; western sandpiper, <i>Calidris mauri</i>; yellow-rumped warbler, <i>Setophaga coronata</i>; Swainson's thrush, <i>Catharus ustulatus</i>) from two families (shorebirds and songbirds) and with different migratory strategies. Ruff and sanderling satellite cells exhibited rapid proliferation, with population doubling times of 9.3±1.3 and 11.4±2.0 hrs whereas the remaining species' cell doubling times were ≥24 hrs. The results indicate that the rapid proliferation of satellite cells is not associated with total migration distance but may be related to flight bout duration and interact with lifespan.</p>