Architecture of the outbred brown fat proteome defines regulators of metabolic physiology.

Brown adipose tissue (BAT) regulates metabolic physiology. However, nearly all mechanistic studies of BAT protein function occur in a single inbred mouse strain, which has limited the understanding of generalizable mechanisms of BAT regulation over physiology. Here, we perform deep quantitative proteomics of BAT across a cohort of 163 genetically defined diversity outbred mice, a model that parallels the genetic and phenotypic variation found in humans. We leverage this diversity to define the functional architecture of the outbred BAT proteome, comprising 10,479 proteins. We assign co-operative functions to 2,578 proteins, enabling systematic discovery of regulators of BAT. We also identify 638 proteins that correlate with protection from, or sensitivity to, at least one parameter of metabolic disease. We use these findings to uncover SFXN5, LETMD1, and ATP1A2 as modulators of BAT thermogenesis or adiposity, and provide OPABAT as a resource for understanding the conserved mechanisms of BAT regulation over metabolic physiology.

Chemical Specification of E3 Ubiquitin Ligase Engagement by Cysteine-Reactive Chemistry.

Targeted protein degradation relies on small molecules that induce new protein-protein interactions between targets and the cellular protein degradation machinery. Most of these small molecules feature specific ligands for ubiquitin ligases. Recently, the attachment of cysteine-reactive chemical groups to pre-existing small molecule inhibitors has been shown to drive specific target degradation. We demonstrate here that different cysteine-reactive groups can specify target degradation via distinct ubiquitin ligases. By focusing on the bromodomain ligand JQ1, we identify cysteine-reactive functional groups that drive BRD4 degradation by either DCAF16 or DCAF11. Unlike proteolysis-targeting chimeric molecules (PROTACs), the new compounds use a single small molecule ligand with a well-positioned cysteine-reactive group to induce protein degradation. The finding that nearly identical compounds can engage multiple ubiquitination pathways suggests that targeting cellular pathways that search for and eliminate chemically reactive proteins is a feasible avenue for converting existing small molecule drugs into protein degrader molecules.

Monocarboxylate transporters facilitate succinate uptake into brown adipocytes.

Uptake of circulating succinate by brown adipose tissue (BAT) and beige fat elevates whole-body energy expenditure, counteracts obesity and antagonizes systemic tissue inflammation in mice. The plasma membrane transporters that facilitate succinate uptake in these adipocytes remain undefined. Here we elucidate a mechanism underlying succinate import into BAT via monocarboxylate transporters (MCTs). We show that succinate transport is strongly dependent on the proportion that is present in the monocarboxylate form. MCTs facilitate monocarboxylate succinate uptake, which is promoted by alkalinization of the cytosol driven by adrenoreceptor stimulation. In brown adipocytes, we show that MCT1 primarily facilitates succinate import. In male mice, we show that both acute pharmacological inhibition of MCT1 and congenital depletion of MCT1 decrease succinate uptake into BAT and consequent catabolism. In sum, we define a mechanism of succinate uptake in BAT that underlies its protective activity in mouse models of metabolic disease.

Neuronal mitochondria transport Pink1 mRNA via synaptojanin 2 to support local mitophagy.

PTEN-induced kinase 1 (PINK1) is a short-lived protein required for the removal of damaged mitochondria through Parkin translocation and mitophagy. Because the short half-life of PINK1 limits its ability to be trafficked into neurites, local translation is required for this mitophagy pathway to be active far from the soma. The Pink1 transcript is associated and cotransported with neuronal mitochondria. In concert with translation, the mitochondrial outer membrane proteins synaptojanin 2 binding protein (SYNJ2BP) and synaptojanin 2 (SYNJ2) are required for tethering Pink1 mRNA to mitochondria via an RNA-binding domain in SYNJ2. This neuron-specific adaptation for the local translation of PINK1 provides distal mitochondria with a continuous supply of PINK1 for the activation of mitophagy.

Nuclear Tau, p53 and Pin1 Regulate PARN-Mediated Deadenylation and Gene Expression.

While nuclear tau plays a role in DNA damage response (DDR) and chromosome relaxation, the mechanisms behind these functions are not fully understood. Here, we show that tau forms complex(es) with factors involved in nuclear mRNA processing such as tumor suppressor p53 and poly(A)-specific ribonuclease (PARN) deadenylase. Tau induces PARN activity in different cellular models during DDR, and this activation is further increased by p53 and inhibited by tau phosphorylation at residues implicated in neurological disorders. Tau's binding factor Pin1, a mitotic regulator overexpressed in cancer and depleted in Alzheimer's disease (AD), also plays a role in the activation of nuclear deadenylation. Tau, Pin1 and PARN target the expression of mRNAs deregulated in AD and/or cancer. Our findings identify novel biological roles of tau and toxic effects of hyperphosphorylated-tau. We propose a model in which factors involved in cancer and AD regulate gene expression by interactions with the mRNA processing machinery, affecting the transcriptome and suggesting insights into alternative mechanisms for the initiation and/or developments of these diseases.

Caracterización técnica y productiva de los sistemas de producción lechera del valle de Sibundoy, Putumayo (Colombia) / Technical and productive characterization of milk production systems in the Sibundoy Valley (Putumayo, Colombia) / Caraterização técnica e produtiva dos sistemas de produção leiteira do vale de Sibundoy, Putumayo (Colômbia)

Resumen En el departamento del Putumayo, el sector ganadero es de gran importancia dentro de la economía, y la producción lechera es el propósito principal de la ganadería en el valle de Sibundoy. Con el objetivo de caracterizar los sistemas de producción lechera en este valle, se realizó un estudio descriptivo de tipo cualitativo, mediante una encuesta dirigida a productores de sistemas lecheros especializados para evaluar aspectos técnicos y productivos. Se encontró que el 79,26 % de los predios tiene menos de 7 ha; el 78,6 % tiene de 2 a 5 animales; la capacidad de carga animal oscila entre 1,14 y 2,92 unidades de gran ganado (UGG); el 45,72 % de los predios son arrendados; en el 80 % de los predios la administración y manejo es realizada por los propietarios con grado de escolaridad bajo (63,7 %); el 48,9 % no posee ningún tipo de instalación ganadera y el 100 % realiza ordeño manual; en su mayoría no llevan registros contables (57,1 a 86,7 %); del 57,1 al 80 % de los tratamientos son realizados por personas diferentes al médico veterinario; el grado de asistencia técnica es muy bajo en el manejo agrícola de praderas y en el administrativo; hay grado bajo en asociatividad, composición del hato, reproducción y manejo de praderas; hay grado medio en uso de la tierra, manejo sanitario, de parto y terneras. Se concluye que los sistemas de producción evaluados son en su mayoría minifundios, con una alta carga animal y un grado bajo de asistencia técnica, lo cual se refleja en la baja eficiencia productiva, reproductiva, sanitaria y administrativa.

Abstract In the department of Putumayo, the livestock sector has a great importance within the economy and dairy production is the main purpose of cattle breeding in the Sibundoy Valley. With the objective of characterizing milk production systems in this valley, a qualitative descriptive study was carried out, using a survey aimed at producers in specialized dairy production systems in order to evaluate different technical and productive aspects. It was found that 79.26% of the parcels have less than 7 ha; 78.6% have 2 to 5 animals; animal load capacity ranges from 1.14 to 2.92 large livestock units (LLU); 45.72% of the parcels are leased; in 80% of the parcels, administration and management is carried out by the owners with a low level of schooling (63.7%); 48.9% do not have any type of livestock installations, and 100% do manual milking; most of them do not keep accounting records (57.1 to 86.7%); 57.1 to 80% of the treatments are performed by persons other than veterinarians; the degree of technical assistance is very low regarding the agricultural as well as administrative management of the grassland; there is a low degree of associativity, composition of the herd, reproduction and grassland management; there is a medium degree of land use, as well as sanitary, labor, and calves management. It is concluded that the production systems evaluated are mostly small landholdings, with a high animal load and a low degree of technical assistance, which is reflected in low productive, reproductive, sanitary, and administrative efficiency.

Resumo No estado de Putumayo, o setor pecuário é de grande importância dentro da economia e a produção leiteira é o propósito principal da pecuária no vale de Sibundoy. Com o objetivo de caracterizar os sistemas de produção de leite neste vale, se realizou um estudo descritivo de tipo qualitativo, por meio de uma enquete dirigida a produtores de sistemas leiteiros especializados para avaliar aspectos técnicos e produtivos. Constatou-se que o 79,26 % dos prédios tem menos de 7 ha; o 78,6 % tem de 2 a 5 animais ; a capacidade de carga animal oscila entre 1,14 e 2,92 unidades de grande gado (UGG); o 45,72 % dos prédios são arrendados; em 80 % dos prédios a administração e manejo é realizada pelos proprietários com grau de escolaridade baixo (63,7 %); o 48,9 % não possui nenhum tipo de instalação pecuária e o 100 % realiza ordenho manual; na maioria dos casos não levam registros contábeis (57,1 a 86,7 %); do 57,1 al 80 % dos tratamentos são realizados por pessoas diferentes ao médico veterinário; o grau de assistência técnica é muito baixo no manejo agrícola de prados e no administrativo; há um baixo grau em associatividade, composição do rebanho, reprodução e manejo de prados; há um grau médio em uso da terra, manejo sanitário, de parto e bezerros. Conclui-se que os sistemas de produção avaliados na maioria são minifúndios, com uma alta carga animal e um baixo grau de assistência técnica, fator que se reflete na baixa eficiência produtiva, reprodutiva, sanitária e administrativa.

Genotoxicidad de Indigofera suffruticosa Mill / Genotocixity of Indigofera suffruticosa Mill

Se estudió el efecto genotóxico de un extracto de Indigofera suffruticosa Mill. mediante el ensayo Salmonella/microsomas con las líneas TA 1535, TA 1537, TA 98 y TA 100 que resultó positivo para el protocolo de incorporación en placas con las cepas TA 1535, TA 1537 con un rango de concentraciones de 50 a 5000 µg/placa (±S9). Mediante el ensayo de inducción de micronúcleos en médula ósea de ratón el extracto exhibió un aumento estadísticamente significativo en la frecuencia de PCE micronucleados en las hembras tratadas y una relación dosis respuesta positiva, cuando se evaluaron dosis de 500, 1000 y 2000 mg/kg por vía oral con el ensayo de micronúcleos en médula ósea de ratón.

It was accomplished the study of the genotoxic effect of extract of Indigofera suffruticosa Mill. using the Salmonella/microsoma assay in strains TA 1535, TA 1537, TA 98 and TA 100 was positive in a plate incorporation protocol with concentrations ranging from 50 to 5000 mg/plate (¡À S9) for the strains TA 1535, TA 1537. The extract of Indigofera suffruticosa Mill. exhibited the significantly increment in the frequency of micronucleated polychromatic erythrocytes in female mice and dose-dependent genotoxicity to mouse bone marrow micronucleus test at the doses of 500, 1000 and 2000 mg/kg assayed.