G is also essential for receptor tyrosine kinase-induced migration of fibroblast and endothelial cells. FGF21 stimulates phosphorylation of fibroblast growth factor receptor substrate 2 and ERK1/2 in the liver. Achondroplasia is a mutation in the fibroblast growth factor receptor 3. FGFR2 is a receptor for fibroblast growth factor. Subsequent work used these factors to induce pluripotency in human fibroblast cells. V-79 (Chinese hamster lung fibroblast) cells. This gene is mainly responsible for making the protein, fibroblast growth factor receptor 3. Achondroplasia is caused by a mutation in fibroblast growth factor receptor 3 ("FGFR3") gene. Gelsolin is a downstream effector of rac for fibroblast motility. This fibroblast proliferation also contracts the tissue. The extracts showed no cytotoxicity against the non-cancerous human fibroblast cell line MRC-5. The fibroblast is the most common cell that creates collagen. Role of Thy-1 in fibrosis and fibroblast differention may have some tissue variation. Pfeiffer syndrome is caused by mutations in the fibroblast growth factor receptors "FGFR1" and "FGFR2". Thus far, it is missing from Xi chromosomes in fibroblast cells.