Question

Which protein in a fibroblast's plasma membrane attaches to the extracellular matrix on the outside of the cell and (through adapter molecules) to actin inside the cell?

Answer 1

Integrin is the protein in a fibroblast's plasma membrane that attaches to the extracellular matrix on the outside of the cell and, through adapter molecules, to actin inside the cell.

Step-by-step explanation:

Integrins are transmembrane proteins found in the plasma membrane of cells, including fibroblasts. They play a crucial role in cell adhesion and signaling. In the context of fibroblasts, integrins facilitate the connection between the cell and the extracellular matrix (ECM). The extracellular domain of integrins binds to specific proteins in the ECM, while the intracellular domain interacts with adapter molecules like talin and vinculin, which in turn link to actin filaments inside the cell.

This linkage forms a structural bridge between the cell's cytoskeleton and the surrounding extracellular environment, enabling processes such as cell movement, tissue integrity, and signal transduction.