Germ cell expression of the transcriptional co-repressor TIF1beta is required for the maintenance of spermatogenesis in the mouse.
The gene for transcriptional intermediary factor 1beta (TIF1beta) encodes a transcriptional co-repressor known to play essential roles in chromatin remodeling as well as in early embryonic development. During spermatogenesis, TIF1beta is preferentially associated with heterochromatin structures of Sertoli cells and round spermatids, as well as with meiotic chromosomes. Its expression is tightly regulated within spermatocyte and spermatid populations, and it is undetectable in spermatogonia. Spatiotemporally controlled ablation of TIF1beta by using a germ cell lineage-specific CreER(T)/loxP system leads to testicular degeneration. This degeneration is not due to impairment of chromatin remodeling processes during meiosis and spermiogenesis, as TIF1beta-deficient spermatocytes are able to complete their differentiation into spermatozoa. It rather occurs as a consequence of shedding of immature germ cells (spermatocytes and spermatids), and disappearance of stem spermatogonia. These results indicate that TIF1beta has important functions in the homeostasis of the seminiferous epithelium, and probably plays a crucial role in the network of paracrine interactions between germ cell subpopulations and/or Sertoli cells.
Weber
Philipp
P
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP/Collège de France, BP163, 67404 Illkirch-cedex, France.
Cammas
Florence
F
Gerard
Christelle
C
Metzger
Daniel
D
Chambon
Pierre
P
Losson
Régine
R
Mark
Manuel
M
D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006570:Heterochromatin / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009687:Nuclear Proteins; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D012708:Sertoli Cells / Q000502:physiology; D013091:Spermatogenesis; D013094:Spermatozoa / Q000502:physiology*; D014157:Transcription Factors; D019076:Transgenes; D000076183:Tripartite Motif-Containing Protein 28
D004268:DNA-Binding Proteins; D006570:Heterochromatin; D009687:Nuclear Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C103190:Trim28 protein, mouse; D000076183:Tripartite Motif-Containing Protein 28