Lipid droplet meets a mitochondrial protein to regulate adipocyte lipolysis.

EMBO J 30 21, 4371–4386 (2011); published online October 07 2011 In response to adrenergic stimulation, adipocytes undergo protein kinase A (PKA)-stimulated lipolysis. A key PKA target in this context is perilipin 1, a major regulator of lipolysis on lipid droplets (LDs). A study published in this issue of The EMBO Journal (Pidoux et al, 2011) identifies optic atrophy 1 (OPA1), a protein that regulates mitochondrial dynamics, as perilipin 1 interaction partner and the A-kinase anchoring protein (AKAP) on LDs that is involved in the induction of stimulated lipolysis.