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Arecco, N.

Publications and source records attributed to Arecco, N..

2 recordsLinked to original sources

The neurodevelopmental disorder-linked PHF14 complex that forms biomolecular condensates detects DNA damage and promotes repair

Numerous chromatin-associated proteins have been linked to neurodevelopmental disorders, yet their molecular functions often remain elusive. PHF14, HMG20A, TCF20 and RAI1 are components of a putative chromatin-associated complex and have been implicated in neurological disorders. Here, we found that Phf14 knockout embryonic stem cells and neural progenitor cells exhibit impaired cell cycle progression and proliferation, inadequate protection of stalled replication forks, and decreased DNA repair. The PHF14 complex rapidly assembles at DNA damage sites and binds to DNA through HMG20A. The PHF14 complex forms DNA-containing phase separated droplets in vitro, where TCF20 facilitates droplet formation. Furthermore, TCF20 maintenance at DNA damage sites is destabilized upon pathological mutation. Our results suggest that the PHF14 complex contributes to DNA damage repair by sensing damaged sites and forming biomolecular condensates, thus supporting cell cycle progression, especially in neural progenitor cells whose spatiotemporal pool is critical for proper brain development.

molecular biology

A temporally controlled sequence of X-chromosomeinactivation and reactivation defines female mouse in vitro germ cells with meiotic potential

The early mammalian germ cell lineage is characterized by extensive epigenetic reprogramming, which is required for the maturation into functional eggs and sperm. In particular, the epigenome needs to be reset before parental marks can be established and then transmitted to the next generation. In the female germ line, reactivation of the inactive X-chromosome is one of the most prominent epigenetic reprogramming events, and despite its scale involving an entire chromosome affecting hundreds of genes, very little is known about its kinetics and biological function. Here we investigate X-chromosome inactivation and reactivation dynamics by employing a tailor-made in vitro system to visualize the X-status during differentiation of primordial germ cell-like cells (PGCLCs) from female mouse embryonic stem cells (ESCs). We find that the degree of X-inactivation in PGCLCs is moderate when compared to somatic cells and characterized by a large number of genes escaping full inactivation. Nevertheless, PGCLCs that fail to undergo X-inactivation show an abnormal gene expression signature and deficiencies in meiotic entry. Subsequent to X-inactivation we observe gradual step-wise X-reactivation, which is mostly completed by the end of meiotic prophase I. Cells deviating from these progressive kinetics and undergoing X-reactivation too rapidly fail to enter a meiotic trajectory. Our data reveals that a fine-tuned X-inactivation and -reactivation cycle is a critical feature of female germ cell developmental competence towards meiosis and oogenesis

developmental biology