Membrane contact sites are regions of close apposition between organelles that facilitate information transfer. Here. we reveal an essential role for Ca2+ derived from the endo-lysosomal system in maintaining contact between endosomes and the endoplasmic reticulum (ER). Antagonizing action of the Ca2+-mobilizing messenger NAADP. https://ashleyshomestores.shop/product-category/4-piece-sectional/