Role of the small GTPase activating protein IQGAP1 in collagen phagocytosis.

Many adult connective tissues undergo continuous remodeling to maintain matrix homeostasis. Physiological remodeling involves the degradation of collagen fibers by the intracellular cathepsin-dependent phagocytic pathway. We considered that a multidomain, small GTPase activating protein, IQGAP1, which is involved in the generation of cell extensions, is required for collagen phagocytosis, possibly arising from its interactions with cdc42 and the actin-binding protein Flightless I (FliI).