Table 1.

Characteristics of matricellular proteins compared with classical extracellular matrix (ECM) proteins.

Classical ECM protein	Matricellular protein
- Structural protein	- Soluble non-structural protein - Low expression level under normal physiological conditions in adult tissues - Induced in almost any tissue by stimuli and disappear after stimulus removal
- Provide a scaffold for stable cell adhesion	- Induce cell motility and tissue remodeling - Various functions via interacting with cell surface receptors, other matrix proteins, growth factors, and cytokines - Knockout mice basically undergo normal development