IMR Press / FBL / Volume 11 / Issue 3 / DOI: 10.2741/1957

Frontiers in Bioscience-Landmark (FBL) is published by IMR Press from Volume 26 Issue 5 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on as a courtesy and upon agreement with Frontiers in Bioscience.

Signaling events during male germ cell differentiation: update, 2006
Show Less
1 Dipartimento di Biologia, Università di Milano, Via Celoria 26, 20133 Milano, Italy
Front. Biosci. (Landmark Ed) 2006, 11(3), 2144–2156;
Published: 1 September 2006

The intracellular transduction of exogenous and cell-autonomous stimuli triggers the transformation of a multipotent stem cell, the spermatogonion, into a highly differentiated, motile and fertile cell, the spermatozoon. This differentiation process is mediated by cell-cell contact and via key players including hormones, growth factors, and cytokines. Female hormones, estrogens and progestins, play a role in the production and functionality of spermatozoon. New findings, however, reconsider the direct action for estrogens on male germ cells while progestins work through non-canonical receptors. Similarly, testosterone, the male hormone, besides acting through its receptor expressed in the somatic cells of testis, seems to work by means of non-classical mechanisms. The recent identification of growth factors, transcriptional regulators, and media for in vitro growth of spermatogonial stem cells should now make it feasible to unravel the entire spermatogenic process. A peculiar feature of the meiotic cycle is the maintenance of condensed chromatin so that DNA duplication is prevented and reduction of genome is achieved. Recently, molecular mechanisms that lead to such a condensation have been discovered. Junctional intercellular complexes between Sertoli and germ cells are critical for coordinating spermatogenesis. Molecular players involved in such cell-cell communication have been identified in Sertoli cells. Now, there is also a need for unravelling the germ cell molecules involved. These issues are the major topics which are discussed here with the goal to suggest a possible answer.

Cell Differentiation
Stem Cells
Steroid Hormones
Transcriptional Regulators
Tyrosine Kinases
Serine/Threonine Kinases
G proteins
Junctional Complex
Back to top