Loss of IP3R (Subramanian et al., 2013b) and STIM (Baumbach et al., 2014) leads to obesity in adult Drosophila. Importantly, adults of a hypomorphic IP3R mutant heteroallelic combination, itprka1091/ug3 (hereafter: itprku) exhibit obesity, starvation resistance and hyperphagia, which are all rescued by overexpression of IP3R in NE cells (Subramanian et al., 2013a). Here, ITPR1 is linked to obesity due to melanocortin 4 receptor deficiency.