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Biology subjects

Meir-Salame, T.

Publications and source records attributed to Meir-Salame, T..

3 recordsLinked to original sources

Cell surface ATP6V1B2 marks a subset of persistent senescent cells with increased resistance to apoptosis

Accumulation of senescent cells promotes ageing and age-related diseases. While senescent cells are heterogenous and increasingly persistent in vivo with age, the mechanisms underlying their heterogeneity, resistance to apoptosis, and tissue accumulation remain insufficiently understood. Here we report that in response to DNA damage, a subset of senescent cells upregulates the v-type ATPase subunit, ATP6V1B2 (V1B2) on the cell surface. This upregulation is associated with altered lysosomal activity and changes in intracellular pH. Heterogeneity of senescent cells marked by cell surface V1B2 (csV1B2) is present in naturally occurring senescent cells within both ageing and fibrotic lungs. Senescent cells expressing csV1B2 show an age-independent transcriptional signature associated with DNA repair and resistance to apoptosis. Consistent with this, we show that csV1B2 expression correlates with senescent cell resistance to ABT-737-induced apoptosis in culture. Our study identifies a subset of senescent cells, marked by csV1B2, with a distinct signature of apoptosis resistance. Understanding the functional heterogeneity of senescent cells and the mechanisms accountable for persistence of specific subpopulations in tissues may facilitate the development of improved senotherapeutic strategies for age-related diseases.

cell biology↗

Natural killer cell function is regulated by TGF-β signaling in pregnancy and tumor progression

The immune compartment of the maternal-fetal interface must balance between supporting maternal-fetal interactions and maintaining maternal tolerance. Despite recent advances, the cellular and molecular regulators that drive maternal immune cell remodeling remain largely unknown. Using index and transcriptional single-cell sorting, we comprehensively characterized the immune compartment dynamics in the maternal-fetal interface of both human and mouse and charted the markers and functional pathways associated with these cells. Comparing immune signatures in decidua and tumors of human and mice, we identify conserved gene modules that are activated in natural killer (NK) cells of both compartments, including TFG-{beta} signaling. Genetic ablation and antibody blockade of the TGF-{beta} pathway in NK cells resulted in enhanced anti-tumor immunity.

immunology↗

A proteome-wide yeast degron collection for the dynamic study of protein function.

Genome-wide collections of yeast strains, known as libraries, revolutionized the way systematic studies are carried out. Specifically, libraries that involve a cellular perturbation, such as the deletion collection, have facilitated key biological discoveries. However, short-term rewiring and long-term accumulation of suppressor mutations often obscure the functional consequences of such perturbations. We present the AID library which supplies "on demand" protein depletion to overcome these limitations. Here, each protein is tagged with a Green Fluorescent Protein (GFP) and an Auxin inducible degron (AID), enabling rapid protein depletion that can be quantified systematically using the GFP element. We characterized the degradation response of all strains and demonstrated its utility by revisiting seminal yeast screens for genes involved in cell cycle progression as well as mitochondrial distribution and morphology. In addition to recapitulating known phenotypes, we also uncovered proteins with previously unrecognized roles in these central processes. Hence, our tool expands our knowledge of cellular biology and physiology by enabling access to phenotypes that are central to cellular physiology and therefore rapidly equilibrated.

cell biology↗