EZR - ezrin | Elisa - Clia - Antibody - Protein

Background

Ezrin is a key protein in the regulation of cell surface structures and functions, playing a critical role in linking the plasma membrane to the actin cytoskeleton. It is a member of the ERM (ezrin, radixin, moesin) protein family, which are involved in cellular processes such as adhesion, migration, and organization of cell surface structures. Ezrin is highly expressed in epithelial cells and is crucial for maintaining the integrity and functionality of the apical membrane domain. Its activity is regulated by phosphorylation and its interaction with phosphatidylinositol-4,5-bisphosphate (PIP2).

Protein Structure

Ezrin is composed of three major domains:

• N-terminal FERM domain: This domain interacts with integral membrane proteins and signaling molecules.
• Central alpha-helical domain: Acts as a flexible linker.
• C-terminal ERM association domain (C-ERMAD): Binds to actin filaments.

Ezrin exists in a dormant conformation where the N-terminal FERM domain interacts with the C-terminal ERMAD, preventing interactions with other proteins. Upon activation, typically through phosphorylation, this conformation opens up, allowing ezrin to link the plasma membrane to the actin cytoskeleton.

Classification and Subtypes

Ezrin is part of the ERM protein family, which includes:

• Radixin
• Moesin

These proteins share structural similarities and functional roles but may be differentially expressed and regulated in various tissues and cell types.

Function and Biological Significance

Ezrin functions primarily as a cross-linker between the plasma membrane and the actin cytoskeleton, impacting various cellular processes:

• Cell Shape and Polarity: By linking membrane proteins to the cytoskeleton, ezrin helps maintain cell shape and polarity.
• Signal Transduction: It participates in signal transduction pathways by interacting with membrane receptors and signaling molecules.
• Cell Adhesion and Migration: Ezrin regulates cell adhesion to the extracellular matrix and is involved in cell migration, which is essential for wound healing and cancer metastasis.

Clinical Issues

• Cancer: Overexpression and aberrant activation of ezrin are associated with various cancers, including osteosarcoma, breast cancer, and colorectal cancer. Ezrin contributes to cancer progression by enhancing cell migration, invasion, and metastasis.
• Congenital Disorders: Mutations in ezrin or its regulatory pathways can lead to congenital disorders affecting epithelial integrity and function.
• Infectious Diseases: Ezrin is exploited by certain pathogens to facilitate their entry and movement within host cells, making it a target for studying infectious disease mechanisms.

Summary

Ezrin is a critical protein that links the plasma membrane to the actin cytoskeleton, regulating cell shape, polarity, adhesion, and migration. It plays significant roles in normal cellular functions and disease processes, particularly in cancer progression and metastasis. Understanding ezrin's structure, regulation, and interactions is essential for developing targeted therapies for diseases associated with its dysfunction. Research continues to explore its broader implications in cell biology and its potential as a therapeutic target.