Heterogeneity of ferrous iron-containing endolysosomes and effects of endolysosome iron on endolysosome numbers, sizes, and localization patterns.

Endolysosomes are key regulators of iron metabolism and are central to iron trafficking and redox signaling. Iron homeostasis is linked to endolysosome acidity and inhibition of endolysosome acidity triggers iron dysregulation. Because of the physiological importance and pathological relevance of ferrous iron (Fe ), we determined levels of Fe specifically and quantitatively in endolysosomes as well as the effects of Fe on endolysosome morphology, distribution patterns, and function.