Cytosolic and Mitochondrial Ca2+ Transients in Mitochondrial Fission Protein MiD49-Defficient Cells

Mitochondrial morphology is the result of balance between mitochondrial fusion and fission processes. mediated by cytosolic GTPase DRP1 which anchored to outer membrane (OMM) MiD49, MiD51, Mff. Changes in due alterations or proteins impact cytoplasmic ([Ca2+]cyt) ([Ca2+]mt) calcium homeostasis. Previous studies from our laboratory showed that cells a patient bearing MiD49 deleterious mutation elongated mitochondria. However, it unclear if ablation alters [Ca2+]cyt [Ca2+]mt homeostasis associated. Mouse embryonic fibroblasts Knock out (KO) cells, p.Q92∗ were transfected with cDNA encoding matrix-targeted fluorescent protein, mt-DsRed, evaluate morphology. To [Ca2+]mt, Ca2+-sensitive mtRCaMP. [Ca2+]cyt, loaded Fluo 4-AM Fura 2-AM. Live-cell imaging was performed using epifluorescence microscopy. Furthermore, potential (ΔΨmt) tested incubating ΔΨmt-sensitive probe, TMRE. The estimulated ATP Histamine. We observed two genotypes studied present upon 100 nM stimulation, WT KO no difference transients amplitude kinetics, consistent comparable resting ΔΨmt. In addition, Histamine (100 mM)-induced patient-derived but patient's displayed increased extrusion kinetics than control individual. Our results suggest protein does not determine homeostasis, Future research needed elucidate role these Drp1 adaptive on intracellular Ca2+