In silico and Wet Bench Interactomics Sheds Light on the Similitudes and Differences between Human ROCO Proteins.

Defining a common and specific function for homologs of a novel protein family is not a trivial task. In their recent study, Tomkins and colleagues have addressed this challenge for the ROCO protein family by exploring interactomes of its four human members: MASL1, DAPK1, LRRK1, and LRRK2. ROCO proteins are characterized by a Ras-GTPase domain embedded in complex multidomain proteins and a functional descriptor for this protein family has been elusive despite accumulating research, particularly for LRRK2, a protein implicated in Parkinson's disease. Tomkins et al. have combined an in silico weighted literature mining approach with novel interactomics data obtained on protein chips for all four proteins under strictly comparable conditions. The combination of these approaches has allowed the prudent formulation of common functions for ROCO proteins, including their involvement in stress response and cell projection organization. In addition, the study also confirms functional specificity for the individual ROCOs with such functions as cell death and apoptosis assigned to DAPK1, cellular, and neuronal development associated with LRRK1 and intracellular transport and organization assigned to LRRK2.