ITPRs (inositol 1,4,5-trisphosphate receptors), the main endoplasmic reticulum (ER) Ca(2+)-release channels, were originally proposed as suppressors of autophagy. Yet, new evidence has accumulated over recent years supporting a crucial, stimulatory role for ITPRs in driving the autophagic flux. Here, we provide an integrated view on how ITPR-mediated Ca(2+) signaling can have a dual impact on autophagy, depending on the characteristics of the spatio-temporal Ca(2+) signals, including the existence of ER-mitochondrial and ER-lysosomal Ca(2+) signaling microdomains.
Keywords: Ca2+ microdomains; Ca2+ signaling; autophagic flux; autophagy; inositol 1,4,5-trisphosphate receptor; spatio-temporal Ca2+ signals.