RESUMEN
<p><b>Objective</b>To study the expression of the gene of myosin regulatory light chain-2 (MYL2) in the development of rat testis tissue.</p><p><b>METHODS</b>Using real-time PCR and immunohistochemistry, we determined the mRNA transcription level and protein expression of MYL2 in the rat testis.</p><p><b>RESULTS</b>The mRNA expression of the MYL2 gene changed in an age-dependent manner, reaching the highest value on postnatal day (PND) 2, then dropped rapidly till PND 8, increased slowly on PNDs 10 and 12, decreased on PND 14, rose slightly from PND 15 and rapidly on PNDs 20 and 25, and declined slowly from PND 65. Immunohistochemistry showed that the MYL2 protein was mainly expressed in testicular sperm cells.</p><p><b>CONCLUSIONS</b>The MYL2 gene may be involved in the proliferation of spermatogonial stem cells and the process of sperm cells developing into mature sperm.</p>