Somatic cell nuclear reprogramming of mouse oocytes endures beyond reproductive decline.
The mammalian oocyte has the unique feature of supporting fertilization and normal development, while capable of reprogramming nuclei of somatic cells toward pluripotency, and occasionally even totipotency. While oocyte quality is known to decay with somatic aging, it is not a given that different biological functions decay concurrently. In this study, we tested whether oocyte's reprogramming ability decreases with aging. We show that oocytes isolated from mice aged beyond the usual reproductive age (climacteric) yield ooplasts that retain reprogramming capacity after somatic nuclear transfer (SCNT), giving rise to higher blastocysts rates compared to young donors ooplasts. Despite the differences in transcriptome between climacteric and young ooplasts, gene expression profiles of SCNT blastocysts were very similar. Importantly, embryonic stem cell lines with capacity to differentiate into tissues from all germ layers were derived from SCNT blastocysts obtained from climacteric ooplasts. Although apoptosis-related genes were down-regulated in climacteric ooplasts, and reprogramming by transcription factors (direct-induced pluripotency) benefits from the inhibition of p53-mediated apoptosis, reprogramming capacity of young ooplasts was not improved by blocking p53. However, more outgrowths were derived from SCNT blastocysts developed in the presence of a p53 inhibitor, indicating a beneficial effect on trophectoderm function. Results strongly suggest that oocyte-induced reprogramming outcome is determined by the availability and balance of intrinsic pro- and anti-reprogramming factors tightly regulated and even improved throughout aging, leading to the proposal that oocytes can still be a resource for somatic reprogramming when they cease to be considered safe for sexual reproduction.
Esteves
Telma Cristina
TC
Max-Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, D-48149 Münster, Germany.
Balbach
Sebastian Thomas
ST
Pfeiffer
Martin Johannes
MJ
Araúzo-Bravo
Marcos Jesus
MJ
Klein
Diana Claire
DC
Sinn
Martina
M
Boiani
Michele
M
D000367:Age Factors; D000375:Aging / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D001755:Blastocyst / Q000166:cytology / Q000502:physiology*; D002460:Cell Line; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D065150:Cellular Reprogramming / Q000235:genetics*; D002979:Climacteric; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005306:Fertilization / Q000235:genetics; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D016158:Genes, p53 / Q000502:physiology; D056084:Genetic Fitness / Q000502:physiology; D006736:Horses; D006801:Humans; D008297:Male; D051379:Mice; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011247:Pregnancy; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D014157:Transcription Factors