0000000000359631
AUTHOR
Carlo Alberto Redi
Gatekeeper of pluripotency: A common Oct4 transcriptional network operates in mouse eggs and embryonic stem cells
Abstract Background Oct4 is a key factor of an expanded transcriptional network (Oct4-TN) that governs pluripotency and self-renewal in embryonic stem cells (ESCs) and in the inner cell mass from which ESCs are derived. A pending question is whether the establishment of the Oct4-TN initiates during oogenesis or after fertilisation. To this regard, recent evidence has shown that Oct4 controls a poorly known Oct4-TN central to the acquisition of the mouse egg developmental competence. The aim of this study was to investigate the identity and extension of this maternal Oct4-TN, as much as whether its presence is circumscribed to the egg or maintained beyond fertilisation. Results By comparing …
Maternal Oct-4 is a potential key regulator of the developmental competence of mouse oocytes
Abstract Background The maternal contribution of transcripts and proteins supplied to the zygote is crucial for the progression from a gametic to an embryonic control of preimplantation development. Here we compared the transcriptional profiles of two types of mouse MII oocytes, one which is developmentally competent (MIISN oocyte), the other that ceases development at the 2-cell stage (MIINSN oocyte), with the aim of identifying genes and gene expression networks whose misregulated expression would contribute to a reduced developmental competence. Results We report that: 1) the transcription factor Oct-4 is absent in MIINSN oocytes, accounting for 2) the down-regulation of Stella, a matern…
Embryonic stem cell differentiation studied by FT-IR spectroscopy
We propose, here, an FT-IR method to monitor the spontaneous differentiation of murine embryonic stem (ES) cells in their early development. Principal component analysis and subsequent linear discriminant analysis enabled us to segregate stem cell spectra into separate clusters corresponding to different differentiation times - and to identify the most significant spectral changes during differentiation. Between days 4 to 7 of differentiation, these spectral changes in the protein amide I band (1700-1600 cm(-1)) and in the nucleic acid absorption region (1050-850 cm(-1)) indicated that mRNA translation was taking place and that specific proteins were produced, reflecting the appearance of a…
Time-Lapse Dynamics of the Mouse Oocyte Chromatin Organisation during Meiotic Resumption
In the mammalian oocyte, distinct patterns of centromeres and pericentromeric heterochromatin localisation correlate with the gamete’s developmental competence. Mouse antral oocytes display two main types of chromatin organisation: SN oocytes, with a ring of Hoechst-positive chromatin surrounding the nucleolus, and NSN oocytes lacking this ring. When matured to MII and fertilised, only SN oocytes develop beyond the 2-cell, and reach full term. To give detailed information on the dynamics of the SN or NSN chromatin during meiosis resumption, we performed a 9 hr time-lapse observation. The main significant differences recorded are: (1) reduction of the nuclear area only in SN oocytes; (2) ~17…
Genome Stability in Embryonic Stem Cells
Paola Rebuzzini1, Maurizio Zuccotti2*, Carlo Alberto Redi1,3 and Silvia Garagna1,4,5* 1Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia Animale, Universita degli Studi di Pavia, Via Ferrata 9, 27100 Pavia, 2Sezione di Istologia ed Embriologia, Dipartimento di Medicina Sperimentale, Universita degli Studi di Parma, Via Volturno 39, 43100 Parma 3Fondazione I.R.C.C.S. Policlinico San Matteo, Piazzale Golgi, 19, 27100 Pavia 4Centro di Ricerca Interdipartimentale di Ingegneria Tissutale, Universita degli Studi di Pavia, Via Ferrata 1, 27100 Pavia 5Centro di Eccellenza in Biologia Applicata, Universita degli Studi di Pavia, Via Ferrata 9, 27100 Pavia Italy
Arsenic trioxide alters the differentiation of mouse embryonic stem cell into cardiomyocytes
AbstractChronic arsenic exposure is associated with increased morbidity and mortality for cardiovascular diseases. Arsenic increases myocardial infarction mortality in young adulthood, suggesting that exposure during foetal life correlates with cardiac alterations emerging later. Here, we investigated the mechanisms of arsenic trioxide (ATO) cardiomyocytes disruption during their differentiation from mouse embryonic stem cells. Throughout 15 days of differentiation in the presence of ATO (0.1, 0.5, 1.0 μM) we analysed: the expression of i) marker genes of mesoderm (day 4), myofibrillogenic commitment (day 7) and post-natal-like cardiomyocytes (day 15); ii) sarcomeric proteins and their orga…