Delta-catenin

Delta-catenin, also known as CTNND2, is a protein that in humans is encoded by the CTNND2 gene. It is a member of the catenin family of proteins, which are involved in the regulation of cell-cell adhesion and signaling.

Structure

Delta-catenin is a member of the armadillo protein family, characterized by the presence of multiple armadillo repeats. These repeats are involved in protein-protein interactions. The protein is composed of several domains, including:

• An N-terminal domain that may be involved in interactions with other proteins.
• A central region containing armadillo repeats, which are crucial for binding to other proteins such as cadherins.
• A C-terminal domain that may be involved in signaling pathways.

Function

Delta-catenin plays a critical role in the regulation of cell-cell adhesion, particularly in the nervous system. It interacts with classical cadherins, such as N-cadherin, to stabilize cell-cell junctions. This interaction is essential for maintaining the structural integrity of tissues.

Role in the Nervous System

In the nervous system, delta-catenin is involved in the development and maintenance of synapses. It is expressed in neurons and is thought to play a role in synaptic plasticity, which is crucial for learning and memory. Delta-catenin may also be involved in the regulation of dendritic spine morphology, influencing the connectivity and function of neural circuits.

Signaling Pathways

Delta-catenin is involved in several signaling pathways, including the Wnt signaling pathway. It can modulate the activity of beta-catenin, another member of the catenin family, which is a key player in the Wnt pathway. Through these interactions, delta-catenin can influence cell proliferation, differentiation, and migration.

Clinical Significance

Mutations in the CTNND2 gene have been associated with several neurological disorders. For example, deletions or mutations in this gene have been linked to cri-du-chat syndrome, a genetic disorder characterized by intellectual disability and developmental delays.

Cancer

Delta-catenin has been implicated in cancer progression. It may play a role in the epithelial-mesenchymal transition (EMT), a process by which epithelial cells acquire mesenchymal, invasive properties. This transition is a key step in the metastasis of cancer cells.

Neurodevelopmental Disorders

Alterations in delta-catenin expression or function have been associated with neurodevelopmental disorders, including autism spectrum disorder and intellectual disability. Research is ongoing to understand the precise mechanisms by which delta-catenin contributes to these conditions.

Research Directions

Current research is focused on elucidating the detailed molecular mechanisms by which delta-catenin regulates cell adhesion and signaling. Understanding these processes may provide insights into the development of therapeutic strategies for diseases associated with delta-catenin dysfunction.

See Also

• Catenin
• Cadherin
• Wnt signaling pathway

External Links

• [UniProt entry for Delta-catenin](https://www.uniprot.org/uniprot/O60716)
• [GeneCards entry for CTNND2](https://www.genecards.org/cgi-bin/carddisp.pl?gene=CTNND2)