Question

Identify extracellular matrix proteins:
(A). Albumin
(B). Fibronectin
(C). Vitronectin
(D). Laminin
Choose the correct answer from the options given below:

• A. (A), (B) and (C) only.
• B. (A), (B) and (D) only.
• C. (A), (B), (C) and (D).
• D. (B), (C) and (D) only.

Hint:

To remember the core ECM proteins, think of the structural and adhesion glycoproteins: Collagen, Elastin, Fibronectin, Laminin, and Vitronectin.
Albumin is always a free-floating plasma protein, never a structural matrix component.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The extracellular matrix (ECM) is a complex structural network surrounding cells in multicellular organisms.
It provides structural support, regulates cell behavior, and facilitates intercellular communication.
The ECM is composed of distinct fibrous proteins and glycosaminoglycans.

Step 2: Detailed Explanation:
- Fibronectin (B): A high-molecular-weight glycoprotein of the ECM that binds to membrane-spanning receptor proteins called integrins.
- Vitronectin (C): An abundant glycoprotein found in the ECM and blood plasma that promotes cell adhesion and spreading.
- Laminin (D): A major glycoprotein of the basal lamina (a specialized layer of the ECM) that plays a crucial role in cell differentiation, migration, and adhesion.
- Albumin (A): The most abundant globular protein in blood plasma, synthesized by the liver, which primarily maintains osmotic pressure and transports substances in circulation rather than serving as an ECM component.
Therefore, Fibronectin, Vitronectin, and Laminin are key extracellular matrix proteins.

Step 3: Final Answer:
The correct answer is (B), (C) and (D) only, corresponding to option (D).