In neuronal dendrites of both rodents and flies, there are regularly spaced contact sites between the endoplasmic reticulum (ER) and plasma membrane, which function as hubs for regulating Ca2+ homeostasis and facilitate long-range transmission of signals along the length of the dendrite. The ladder-like patterning of the neuronal ER and its plasma membrane junctions resembles that of the sarcoplasmic reticulum-plasma membrane junctions in muscles.