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Raimondo, D.

Publications and source records attributed to Raimondo, D..

4 recordsLinked to original sources

Identifying and ranking species that need urgent management action to achieve Target 4 of the Global Biodiversity Framework

Target 4 of the Kunming-Montreal Global Biodiversity Framework (KMGBF) calls for urgent management actions to halt humaninduced extinctions and enable species recovery. However, most Parties face substantial challenges in determining which species require urgent management actions. Here, we present a transparent, standardised protocol that identifies and ranks species most likely to need urgent management actions at the national level, using globally available data from the IUCN Red List of Threatened Species. The protocol integrates four criteria aligned with Target 4: global extinction risk, rate of decline, population or range restriction, and endemism, to generate a national ranked list of species. Species scoring highly on these four criteria, and therefore most in need of urgent management action, are ranked most highly. We applied this method to all 250 countries and territories listed in the IUCN Red List and pilottested national rankings with participants from eight diverse countries. Across pilots, participants reported that the ranked lists were scientifically robust, timesaving, and valuable starting points for national prioritysetting, while stating the importance of national context, and the need for additional technical and financial support for implementation. Our results demonstrate that a sciencebased approach can meaningfully support Parties in identifying species requiring urgent action under Target 4, in a standardised way. With 2030 approaching rapidly, this protocol provides an immediate, practical tool to accelerate progress toward halting extinctions and advancing species recovery.

ecology↗

Exploring the mechanism and pattern of bone formation during RANKL inhibition in a mouse model of fibrous dysplasia

Fibrous dysplasia (FD) of bone is a genetic fibro-osseous disorder with increased bone remodeling activity. Inhibition of RANKL modifies FD lesions by inducing the replacement of the fibrous tissue with bone. This effect was observed in FD murine models receiving anti-mouse RANKL antibodies or small molecule RANKL inhibitors and in FD patients treated with denosumab. However, in neither case the mechanism and pattern of deposition of the newly formed bone were clarified. We performed radiographic, morphological and molecular analyses on EF1-GsR201C (FD) mice receiving an anti-mouse RANKL antibody. We observed that RANKL inhibition caused a decrease in the expression of genes involved in osteogenesis, osteoclastogenesis, matrix remodeling and osteoblast-osteoclast cross-talk in affected skeletal segments. Nonetheless, intra-lesional bone surfaces were covered by a continuous layer of osteoid, indicating that bone formation was actively ongoing in the pathological tissue in spite of the treatment. Accordingly, all bone surfaces within FD lesions showed calcein labeling which was never detected in the fibrous tissue far from bone. These results indicate that in the absence of RANKL activity, bone formation in FD tissue does not occur diffusely or stochastically. In contrast, it is restricted to bone surfaces where osteoprogenitor cells are orderly recruited from the adjacent fibrosis, progressively converting it into bone. Clinically, this suggests that the volume of pre-treatment bone in FD lesions may be a determinant of the skeletal improvement that individual patients may achieve during the same denosumab treatment course. As a consequence, it may also be a determinant of the severity of the rebound effect that they can experience upon treatment discontinuation.

pathology↗

Preventing extinctions post-2020 requires recovery actions and transformative change

Stopping human-induced extinctions will require strong policy commitments that comprehensively address threats to species. In 2021, a new Global Biodiversity Framework will be agreed by the Convention on Biological Diversity. Here we investigate how the suggested targets could contribute to reducing threats to threatened vertebrates, invertebrates, and plants, and assess the importance of a proposed target to implement recovery actions for threatened species. We find that whilst many of the targets benefit species, extinction risk for over one third of threatened species would not be reduced sufficiently without a target on recovery actions, including ex situ conservation, reintroductions and other species-specific interventions. A median of 41 threatened species per country require such actions, and they are found in most countries of the world. To prevent future extinctions, policy commitments must include recovery actions for the most threatened species in addition to broader transformative change.

ecology↗

Human AKTIP interacts with ESCRT proteins and functions at the midbody in cytokinesis

To complete mitosis, the intercellular bridge that links daughter cells needs to be cleaved. This abscission step is carried out by the sequential recruitment of ESCRT proteins at the midbody. We report here that a new factor, named AKTIP, works in association with ESCRTs. We find that AKTIP binds to the ESCRT I subunit VPS28, and show by high resolution microscopy that AKTIP forms a ring in the dark zone of the intercellular bridge. This ring is positioned in between the circular structures formed by ESCRTs type III. Functionally, we observe that the reduction of AKTIP impinges on the recruitment of the ESCRT III member IST1 at the midbody and causes abscission defects. Taken together, these data indicate that AKTIP is a new factor that contributes to the formation of the ESCRT complex at the midbody and is implicated in the performance of the ESCRT machinery during cytokinetic abscission.

cell biology↗