Formation of Mobile Chromatin-Associated Nuclear Foci Containing HIV-1 Vpr and VPRBP Is Critical for the Induction of G2 Cell Cycle Arrest

HIV-1 Viral protein R (Vpr) induces a cell cycle arrest at the G2/M phase by activating the ATR DNA damage/stress checkpoint. Recently, we and several other groups showed that Vpr performs this activity by recruiting the DDB1-CUL4A (VPRBP) E3 ubiquitin ligase. While recruitment of this E3 ubiquitin ligase complex has been shown to be required for G2 arrest, the subcellular compartment where this complex forms and functionally acts is unknown. Herein, using immunofluorescence and confocal microscopy, we show that Vpr forms nuclear foci in several cell types including HeLa cells and primary CD4+ T-lymphocytes. These nuclear foci contain VPRBP and partially overlap with DNA repair foci components such as γ-H2AX, 53BP1 and RPA32. While treatment with the non-specific ATR inhibitor caffeine or depletion of VPRBP by siRNA did not inhibit formation of Vpr nuclear foci, mutations in the C-terminal domain of Vpr and cytoplasmic sequestration of Vpr by overexpression of Gag-Pol resulted in impaired formation of these nuclear structures and defective G2 arrest. Consistently, we observed that G2 arrest-competent sooty mangabey Vpr could form these foci but not its G2 arrest-defective paralog Vpx, suggesting that formation of Vpr nuclear foci represents a critical early event in the induction of G2 arrest. Indeed, we found that Vpr could associate to chromatin via its C-terminal domain and that it could form a complex with VPRBP on chromatin. Finally, analysis of Vpr nuclear foci by time-lapse microscopy showed that they were highly mobile and stable structures. Overall, our results suggest that Vpr recruits the DDB1-CUL4A (VPRBP) E3 ligase to these nuclear foci and uses these mobile structures to target a chromatin-bound cellular substrate for ubiquitination in order to induce DNA damage/replication stress, ultimately leading to ATR activation and G2 cell cycle arrest

Archeohandi: protocol for a national disabilities database in archaeology in France

The archaeology of disability is a relatively recent and little-known approach in France. While the study of palaeopathology now goes hand in hand with funerary archaeology and osteoarchaeology, the French study of disabilities and disabling pathologies remains marginal and unevenly treated, depending on location, chronology and researcher’s interest. This paper focuses on highlighting the compatibility between this new research area, the obligations of osteoarchaeology, and the benefits of developing a national, diachronic, and interdisciplinary study. A database is designed within an interpretive, consensual framework, that can be adapted to overcome limitations and promote open-minded research on the care of the disabled in their own communities. A preliminary category selection of disabling pathologies has been made. These are trepanation, completely edentulous and/or compensating denture, neuronal impairment, severe scoliosis, Paget's disease, Diffuse Idiopathic Skeletal Hyperostosis (DISH), rickets, dwarfism, infectious diseases, unreduced fracture, amputation, severe degenerative disease and others. This list has been critically reviewed by experts in the field; it will evolve in a somewhat Darwinian fashion. Our database is hosted on the Huma-Num platform, with a management interface and quick access based on multiple tabs. The data includes information about archaeological operations, subjects, and pathologies; it is complemented by pictorial data stored on the Nakala platform. The development involved creating a prototype using HTML, CSS, JavaScript, SQL, and PHP, with features to display, add, modify, and delete operations and subjects. Enhancements have been made, including search optimization, charts, and the ability to export data in CSV format. The database, whose administrative interface can be accessed at archeohandi.huma-num.fr, contains so far 211 existing operations with a total of 1232 registered subjects spread throughout metropolitan France. These initial data reveal numerous research perspectives in osteoarchaeology that can be combined with other research topics, such as virtual reality

CARACTERISATION DU RECEPTEUR DE LA PROLACTINE CHEZ LA TRUITE ARC-EN-CIEL (ONCORHYNCHUS MYKISS). CLONAGE DE L'ADN COMPLEMENTAIRE CODANT POUR CE RECEPTEUR ET ETUDE DE LA REGULATION DE L'EXPRESSION DU GENE DANS LES ORGANES DE L'OSMOREGULATION

RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

Effets des macrolides et des glucocorticoïdes sur l'inflammation pulmonaire dans la mucoviscidose

La mucoviscidose (ou CF pour Cystic Fibrosis) est la maladie génétique la plus fréquente en France. Le gène responsable de la maladie code pour un canal chlorure nommé CFTR pour cystic fibrosis transmembrane conductance regulator. La principale cause de décès des patients est liée à l inflammation et aux infections pulmonaires chroniques. Cette inflammation est caractérisée, entre autres, par la production excessive de médiateurs inflammatoires tels que l interleukine (IL)-8. Afin de mieux orienter les stratégies thérapeutiques utilisées actuellement, nous avons étudié les mécanismes moléculaires impliqués dans la réponse anti-inflammatoire des macrolides et des glucocorticoïdes dans des cellules bronchiques CF. Dans un premier temps, nous avons montré que l azithromycine n inhibe pas la sécrétion d'IL-8 dans les cellules CF, et qu elle n a aucun effet sur les voies pro-inflammatoires NF- B et MAPK. De manière intéressante, nous avons démontré que l azithromycine active et restaure les efflux chlorure dans les cellules CF. Dans la seconde partie de notre travail, nous avons mis en évidence que la dexaméthasone inhibe la sécrétion d IL-8 dans les cellules CF, en agissant sur les voies NF- B et MAPK. Nous avons également démontré l effet synergique de la dexaméthasone et d un inhibiteur de p38 MAPK sur la sécrétion d IL-8. L ensemble de ces résultats souligne l importance d étudier précisément les mécanismes moléculaires impliqués dans l inflammation pulmonaire dans la mucoviscidose afin d optimiser les stratégies thérapeutiques pour les patientsPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Transfer of Tilapia (Oreochromis niloticus) to a hyperosmotic environment is associated with sustained expression of prolactin receptor in intestine, gill, and kidney

International audienceExpression of the tilapia prolactin receptor (tiPRL-R) has been characterized in the intestine of Oreochromis niloticus and the levels of both tiPRL-R transcripts and tiPRL binding sites have been further analyzed in this organ, as well as in gill and kidney, during adaptation of tilapia to a hyperosmotic environment. A single high-affinity binding site for tilapia PRL-I (tiPRL-I) was determined in full-length intestine by Scatchard analysis. A heterogeneous distribution of tiPRL-R was detected in this organ, with the posterior part always displaying a higher expression of both tiPRL-R transcript and tiPRL binding sites than the anterior and medial parts. Transfer of tilapia to brackish water (BW) led to an apparent increase in the specific binding of tiPRLs in intestine and gill even for long-term-adapted fish, whereas the high level of kidney tiPRL binding sites measured in control fish reared in fresh water was still detected in BW-adapted tilapia. There was no overall significant modification of tiPRL-R transcript levels in any organ during short-term or long-term adaptation, although a limited decrease occurred in the gill of BW-adapted fish, as shown earlier. Therefore, in O. niloticus adapted to BW, high and sustained levels of ti-PRL-R were observed in the three major osmoregulatory organs, gill, kidney, and intestine

Expression of the prolactin receptor (tiPRL-R) gene in tilapia Oreochromis niloticus : tissue distribution and cellular localization in osmoregulatory organs

International audienc

Molecular characterization of prolactin and cortisol receptors in fish

International audienc

Expression of the prolactin receptor (tiPRL-R) gene in tilapia Oreochromis niloticus : tissue distribution and cellular localization in osmoregulatory organs

International audienc

Translating the genetics of cystic fibrosis to personalized medicine

International audienceCystic fibrosis (CF) is the most common life-threatening recessive genetic disease in the Caucasian population. This multiorgan disease is caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein, a chloride channel recognized as regulating several apical ion channels. The gene mutations result either in the lack of the protein at the apical surface or in an improperly functioning protein. Morbidity and mortality because of the mutation of CFTR are mainly attributable to lung disease resulting from chronic infection/inflammation. Since its discovery as the causative gene in 1989, much progress has been achieved not only in clinical genetics but also in basic science studies. Recently, combinations of these efforts have been successfully translated into development and availability for patients of new therapies targeting specific CFTR mutations to correct the CFTR at the protein level. Current technologies such as next gene sequencing and novel genomic editing tools may offer new strategies to identify new CFTR variants and modifier genes, and to correct CFTR to pursue personalized medicine, which is already developed in some patient subsets. Personalized medicine or P4 medicine (“personalized,” “predictive,” “preventive,” and “participatory”) is currently booming for CF. The various current and future challenges of personalized medicine as they apply to the issues faced in CF are discussed in this review

Molecular characterization of prolactin receptor (PRLR) in fish

National audienc