Crossing the Red Sea: phylogeography of the hamadryas baboon, Papio hamadryas hamadryas

International audienceThe hamadryas baboon (Papio hamadryas hamadryas) is found both in East Africa and western Arabia and is the only free-ranging nonhuman primate in Arabia. It has been hypothesized that hamadryas baboons colonized Arabia in the recent past and were possibly even transported there by humans. We investigated the phylogeography of hamadryas baboons by sequencing a portion of the control region of mtDNA in 107 baboons from four Saudi Arabian populations and combing these data with published data from Eritrean (African) P. h. hamadryas. Analysis grouped sequences into three distinct clades, with clade 1 found only in Arabia, clade 3 found only in Africa, but clade 2 found in both Arabian and African P. h. hamadryas and also in the olive baboon, P. h. anubis. Patterns of variation within Arabia are neither compatible with the recent colonization of Arabia, implying that baboons were not transported there by humans, nor with a northerly route of colonization of Arabia. We propose that hamadryas baboons reached Arabia via land bridges that have formed periodically during glacial maxima at the straits of Bab el Mandab in the southern Red Sea. We suggest that the genetic differentiation of Arabian from African populations suggests that Arabian populations have a higher conservation status than recognized previously

The response of commensal hamadryas baboons to seasonal reduction in food provisioning

En haut de la falaise de Al Hada, les automobilistes de passage nourrissent quotidiennement les babouins et une grande troupe de Papio hamadryas vit principalement de cette manne. La croissance de cette troupe de singes commensaux préoccupe les autorités locales qui aimeraient en limiter l'effectif. La solution la plus directe serait l'interdiction de nourrir les animaux, poussant ainsi les babouins à exploiter la végétation naturelle, mais la qualité des ressources naturelles et la capacité des babouins à les utiliser restent incertaines. La réponse à une réduction de l'apport alimentaire a été étudiée pendant que la route était fermée pour réparation en hive

Management of commensal baboons in Saudi Arabia

Avec le récent développement urbain dans les montagnes du sud-ouest saoudien, certaines populations locales de Papio hamadryas sont devenues dépendantes de l'homme pour leur subsistance. Nous avons mené une analyse globale de la situation et des origines des conflits homme/babouins en Arabie Saoudite. Parmi les solutions pratiques pour résoudre les situations de conflit, nous avons proposé et expérimenté la réduction du taux de reproduction par vasectomie des mâles et implantation hormonale des femelles, l'usage de matériel d'effarouchement acoustique (canon à gaz modifié) et de chiens spécialement entraînés. Un programme d'action a été mis en place comprenant des solutions à court terme pour parer aux situations de conflit déjà installées et des actions à long terme pour supprimer les causes fondamentales du commensalisme en Arabi

Could Work Be a Source of Behavioural Disorders? A Study in Horses

Stress at work, as shown by a number of human studies, may lead to a variety of negative and durable effects, such as impaired psychological functioning (anxiety, depression…). Horses share with humans this characteristic of working on a daily basis and are submitted then to work stressors related to physical constraints and/or more “psychological” conflicts, such as potential controversial orders from the riders or the requirement to suppress emotions. On another hand, horses may perform abnormal repetitive behaviour (“stereotypies”) in response to adverse life conditions. In the present study, we investigated whether the type of work the horses are used for may have an impact on their tendency to show stereotypic behaviour (and its type) outside work. Observations in their box of 76 horses all living in the same conditions, belonging to one breed and one sex, revealed that the prevalence and types of stereotypies performed strongly depended upon the type of work they were used for. The stereotypies observed involved mostly mouth movements and head tossing/nodding. Work constraints probably added to unfavourable living conditions, favouring the emergence of chronic abnormal behaviours. This is especially remarkable as the 23 hours spent in the box were influenced by the one hour work performed every day. To our knowledge, this is the first evidence of potential effects of work stressors on the emergence of abnormal behaviours in an animal species. It raises an important line of thought on the chronic impact of the work situation on the daily life of individuals

Etude du pâturage mixte caprins, bovins en Martinique

L'étude du régime alimentaire de caprins et de bovins conduits en pâturage mixte sur des savanes naturelles plus ou moins dégradées, permet de montrer que la compétition avec les bovins pousse les caprins vers la consommation accrue des espèces indésirables sur les pâturages. La complémentarité alimentaire des deux espèces permet d'obtenir une charge plus élevée tout en évitant l'embroussaillement des parcelles.</jats:p

Influenza A virus co-opts ERI1 exonuclease bound to histone mRNA to promote viral transcription.

Cellular exonucleases involved in the processes that regulate RNA stability and quality control have been shown to restrict or to promote the multiplication cycle of numerous RNA viruses. Influenza A viruses are major human pathogens that are responsible for seasonal epidemics, but the interplay between viral proteins and cellular exonucleases has never been specifically studied. Here, using a stringent interactomics screening strategy and an siRNA-silencing approach, we identified eight cellular factors among a set of 75 cellular proteins carrying exo(ribo)nuclease activities or involved in RNA decay processes that support influenza A virus multiplication. We show that the exoribonuclease ERI1 interacts with the PB2, PB1 and NP components of the viral ribonucleoproteins and is required for viral mRNA transcription. More specifically, we demonstrate that the protein-protein interaction is RNA dependent and that both the RNA binding and exonuclease activities of ERI1 are required to promote influenza A virus transcription. Finally, we provide evidence that during infection, the SLBP protein and histone mRNAs co-purify with vRNPs alongside ERI1, indicating that ERI1 is most probably recruited when it is present in the histone pre-mRNA processing complex in the&nbsp;nucleus.</p

SUV39H1 Ablation Enhances Long-term CAR T Function in Solid Tumors.

Failure of adoptive T-cell therapies in patients with cancer is linked to limited T-cell expansion and persistence, even in memory-prone 41BB-(BBz)-based chimeric antigen receptor (CAR) T cells. We show here that BBz-CAR T-cell stem/memory differentiation and persistence can be enhanced through epigenetic manipulation of the histone 3 lysine 9 trimethylation (H3K9me3) pathway. Inactivation of the H3K9 trimethyltransferase SUV39H1 enhances BBz-CAR T cell long-term persistence, protecting mice against tumor relapses and rechallenges in lung and disseminated solid tumor models up to several months after CAR T-cell infusion. Single-cell transcriptomic (single-cell RNA sequencing) and chromatin opening (single-cell assay for transposase accessible chromatin) analyses of tumor-infiltrating CAR T cells show early reprogramming into self-renewing, stemlike populations with decreased expression of dysfunction genes in all T-cell subpopulations. Therefore, epigenetic manipulation of H3K9 methylation by SUV39H1 optimizes the long-term functional persistence of BBz-CAR T cells, limiting relapses, and providing protection against tumor rechallenges. Limited CAR T-cell expansion and persistence hinders therapeutic responses in solid cancer patients. We show that targeting SUV39H1 histone methyltransferase enhances 41BB-based CAR T-cell long-term protection against tumor relapses and rechallenges by increasing stemness/memory differentiation. This opens a safe path to enhancing adoptive cell therapies for solid tumors. See related article by Jain et al., p. 142. This article is featured in Selected Articles from This Issue, p. 5