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Block, E.

Publications and source records attributed to Block, E..

2 recordsLinked to original sources

LDO proteins and Vac8 form a vacuole-lipid droplet contact site required for lipophagy in response to starvation

Lipid droplets (LDs) are fat storage organelles critical for energy and lipid metabolism. Upon nutrient exhaustion, cells consume LDs via gradual lipolysis or via lipophagy, the en bloc uptake of LDs into the vacuole. Here, we show that LDs dock to the vacuolar membrane via a contact site that is required for lipophagy in yeast. The LD-localized LDO proteins carry an intrinsically disordered region that associates with vacuolar Vac8 to form vCLIP, the vacuolar-LD contact site. Nutrient limitation drives vCLIP formation, and its inactivation blocks lipophagy. Vac8 is sufficient to recruit LDs to cellular membranes. We establish a functional link between lipophagy and microautophagy of the nucleus, both requiring Vac8 to form respective contact sites upon metabolic stress. In sum, we unravel the molecular architecture of vCLIP, a contact site required for lipophagy, and find that Vac8 provides a platform for multiple and competing contact sites associated with autophagy.

cell biology↗

Semiochemical responsive olfactory sensory neurons are sexually dimorphic and plastic

AbstractUnderstanding how genes and experiences work in concert to generate phenotypic variability will provide a better understanding of individuality. Here, we considered this in the context of the main olfactory epithelium, a chemosensory structure with over a thousand distinct cell-types, in mice. We identified a subpopulation of at least three types of olfactory sensory neurons, defined by receptor expression, whose abundances were sexually dimorphic. This subpopulation of olfactory sensory neurons was over-represented in sex-separated female mice and responded robustly to the male-specific semiochemicals 2-sec-butyl-4,5-dihydrothaizole and (methylthio)methanethiol. Sex-combined housing led to a robust attenuation of the female over-representation. Testing of Bax null mice revealed a Bax-dependence in generating the sexual dimorphism in sex-separated mice. Altogether, our results suggest a profound role of experience in influencing homeostatic neural lifespan mechanisms to generate a robust sexually dimorphic phenotype in the main olfactory epithelium.

neuroscience↗