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Corti, P.

Publications and source records attributed to Corti, P..

2 recordsLinked to original sources

Misuse of Historical Data to Determine Past Distribution Range and Migratory Patterns of the Patagonian Huemul Misleads Conservation Targets

Historical information is widely used to understand mammals distribution dynamics and drivers, and it has been worldwide acknowledged by conservation programmes. Although these records have some limitations such as spatial and temporal accuracy, non-standardized sampling, geographical imprecisions, and levels of bias, they can fulfil a useful function to set reference conditions, priorities, and conservation goals. In the case of huemul (Hippocamelus bisulcus), an endemic cervid of shrubby and forested habitats from the Andes Mountains of southern Argentina and Chile, some reports suggest its historical presence in the steppe biome. This led Flueck et al. (2022) to assume that the past distribution of the huemul extended as far as the Atlantic coast and even in Tierra del Fuego, proposing that the altitudinal migratory tradition has been broken. Here, we carried out a qualitative and quantitative analysis of the written sources used by the authors to support their assumptions. We conclude that there are errors, uncertainties, and questionable interpretations on the use of historical data that do not add more value, instead, add mostly confusion with the misleading potential of conservation efforts on huemul.

zoology↗

Myoglobin promotes cardiomyocyte differentiation through oxidatively modulating the Hippo Kinase Pathway

BackgroundWhile cardiomyocytes undergo terminal differentiation postnatally and rarely re-enter the cell cycle, the endogenous mechanisms that propagate differentiation and prevent de-differentiation remain unclear. The monomeric heme protein myoglobin, which stores oxygen and regulates reactive oxygen/nitrogen species balance in the heart, increases in expression by over 50% during cardiomyocyte differentiation. Though myoglobin deletion without significant compensation is embryonic lethal in mice, a role for the protein in regulating cardiomyocyte differentiation has not been tested. We hypothesized that myoglobin expression is required for cardiomyocyte differentiation and the loss of myoglobin enables de-differentiation. MethodsMyoglobin was genetically silenced in HL-1, H9C2 cells, and neonatal rat ventricular cardiomyocytes (NRVM) to examine myoglobin-dependent effects on differentiation, proliferation, and Hippo pathway signaling. A zebrafish model of Mb depletion was made using CRISPR-Cas9 to test the effect of myoglobin depletion on cardiac regeneration after apical resection injury in vivo. ResultsMyoglobin deletion in cultured cell lines and NRVM decreased the gene expression of cardiomyocyte differentiation markers (troponin, myosin light chain, and myosin heavy chain), upregulated markers of dedifferentiation (runx1 and dab2) and stimulated cell proliferation. Mechanistically, we show that the heme prosthetic group of myoglobin catalyzes the oxidation of the Hippo pathway kinase LATS1, which activates the enzyme to phosphorylate the downstream Yes-associated protein (YAP) transcription factor, which prevents its transcriptional activity. Thus, the loss of myoglobin results in the de-phosphorylation and nuclear translocation of YAP, which propagates proliferation and fetal gene expression. In vivo, myoglobin-deficient zebrafish hearts recapitulated the increase in YAP signaling and showed accelerated regeneration at 20 days post apical injury. ConclusionWe a novel role for myoglobin as an endogenous driver of cardiomyocyte differentiation, and a regulator of the Hippo pathway. These findings suggest myoglobin as a potential target for strategies to enhance cardiac development and improve cardiac repair and regeneration.

cell biology↗