Differences between germ-line stem cells and multipotent adult germ-line stem cells for microRNAs

Abstract

Testes-derived male germ-line stem cells exhibit spermatogenic potential or multipotency depending on the culture conditions used for their isolation and in vitro maintenance. While unipotent male germ-line stem (GS) cells has the potential to repopulate the empty seminiferous tubules of infertile males, multipotent adult germ-line stem (maGS) cells have the ability to differentiate into cells of all three germ layers for their application in regenerative medicine. Unfortunately, co-existence of both types of stem cells in a cell population may limit their bio-medical, clinical and research application. In particular, testicular transplantation of GS cells with contaminating maGS cells may result in teratoma formation. Recent studies have revealed that endogenous small non-coding microRNA (miRNA) play important roles in the conversion of GS cells into maGS cells and may form a miRNA signature that may be used as a molecular tool to distinguish the GS cells from maGS cells. This chapter describes the biogenesis and functions of miRNAs in the context of testes-derived male germ-line stem cells and discusses their potential application in distinguishing the unipotent GS cells from the multipotent maGS cells.