Difference Between Cadherin and Integrin

The key difference between cadherin and integrin is that cadherin is a cell adhesion molecule that is mainly important in cell to cell adhesion, while integrin is a cell adhesion molecule that is mainly important in cell to extracellular matrix adhesion.

Cell adhesion molecules are proteins located on the cell surface. They are involved in binding cells with other cells or with the extracellular matrix. Cell adhesion is a very crucial component in maintaining tissue structure and function. These molecules help hold animal cells together. Apart from serving as molecular glue, cell adhesion molecules also help in cellular growth, contact inhibition, and apoptosis. Sometimes, the aberrant expression of cell adhesion molecules results in pathologies such as frostbite and cancer. Therefore, cadherin and integrin are two types of calcium-dependent cell adhesion molecules.

CONTENTS

1. Overview and Key Difference
2. What is Cadherin 
3. What is Integrin
4. Similarities – Cadherin and Integrin
5. Cadherin vs Integrin in Tabular Form
6. Summary

What is Cadherin?

Cadherin is a cell adhesion molecule that is mainly important in cell-to-cell adhesion. It is also very important in the formation of adherens junctions. Cadherin is a class of type I transmembrane proteins. Calcium ions are very important for the function of cadherin. The cell to cell adhesion is mediated by extracellular cadherin domains while the intracellular cytoplasmic tail is associated with cadherin adhesome. The members of the cadherin family are essential for maintaining cell to cell contact and also for regulating cytoskeletal complexes. The cadherin superfamily includes protocadherins, desmogleins, and desmocollins, etc. They all share the cadherin repeats, which are the extracellular calcium-binding domains.

Cadherin behaves as both a receptor and ligand for other molecules. It helps the proper positioning of cells during the development process.  It also assists the separation of the different tissue layers and cellular migration. Furthermore, E-cadherins are crucial in several processes of embryogenesis, such as gastrulation, neurulation, and organogenesis. However, the loss of function of E-cadherins increases the invasiveness and metastasis of tumors.

What is Integrin?

Integrin is a cell adhesion molecule that is mainly important in cell to extracellular matrix adhesion. It is a transmembrane receptor that mainly facilitates the cell to extracellular matrix adhesion. Upon ligand binding, it activates various signal transduction pathways that mediate different cellular functions such as regulation of the cell cycle, organization of the intracellular cytoskeleton, movement of new receptors to the cell membrane. The presence of integrins helps rapid and flexible responses to different events on the cell surface. 24 different types of intergrins are present in vertebrates. Some of them are α1β1, α2β1, α3β1, α4β1, α5β1, α6β1, α7β1, αLβ2, αVβ1, etc.

Integrin is an obligate heterodimer. Integrin is found in all animals cells while integrin-like receptors can be found in plants cells. It has two main functions: the attachment of the cells to the extracellular matrix (ECM) and signal transduction from ECM to the cells. It also involves biological activities such as extravasation, cell to cell adhesion, cell migration, acts as receptors for several viruses such as adenovirus, echovirus, hantavirus, poliovirus, etc. In addition, it plays a pivotal role in blood clot formation. The ligands for integrin include fibronectin, vitronectin, collagen, and laminin.

What are the Similarities Between Cadherin and Integrin?

• Cadherin and integrin are cell adhesion molecules.
• Both are proteins.
• They are calcium-dependent.
• Their abnormal expression causes cancer.
• Both of them can be receptors for various ligands.

What is the Difference Between Cadherin and Integrin?

Cadherin is a cell adhesion molecule that is mainly important in cell to cell adhesion while integrin is a cell adhesion molecule that is mainly important in cell to extracellular matrix adhesion. So, this is the key difference between cadherin and integrin. Furthermore, cadherin is a homodimer, while integrin is a heterodimer.

The following infographic lists the differences between cadherin and integrin in tabular form.

Summary – Cadherin vs Integrin

Cell adhesion molecules are proteins that directly participate in the adhesion of one cell to another or to the extracellular matrix. Cadherin and integrin are two types of calcium-dependent cell adhesion molecules. Cadherin is mainly important in cell to cell adhesion while integrin is mainly important in cell to extracellular matrix adhesion. Thus, this is the summary of the difference between cadherin and integrin.

Reference:

1.“Cadherins.” An Overview | ScienceDirect Topics.
2. “What Is Integrin?” MBInfo.

Image Courtesy:

1. “Figure 04 06 04” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia
2. “Figure 1 – Nieuwenhuis et al 2018 – Integrins promote axonal regeneration after injury of the nervous system – Biological Reviews – doi 10.1111-brv.12398” By Nieuwenhuis, B., Haenzi, B., Andrews, M. R., Verhaagen, J. and Fawcett, J. W. (2018) . doi:10.1111/brv.12398 (CC BY 4.0) via Commons Wikimedia