Dual mechanism model for the activity of Trpml. (A) Diagram of a cell that either migrates or engulfs cell debris. (B) When the hemocyte is migrating, the lysosomes displace toward the rear, releasing calcium ions locally, which bind calmodulin and activate Myosin Light Chain Kinase (MLCK), which in turn phosphorylates Sqh (MLC). The counterbalance is regulated by the Myosin Light Chain Phosphatase (MLCP) trimeric complex, composed of Protein Phosphatase 1β (PPIβ), Myosin binding subunit (Mbs) and Myosin phosphatase targeting subunit 75D (Mypt). (C) After closure of the phagocytic cup, the phagosome is formed and fuses with the lysosome via v-SNARE (Vamp7) and t-SNARE complex formation in a calcium-dependent manner, generating the phagolysosome. Here, the engulfed material is degraded by the action of lysosomal proteases.