OPCML - opioid binding protein/cell adhesion molecule like| Elisa - Clia - Antibody - Protein

Background

Opioid binding protein/cell adhesion molecule-like (OPCML) is a member of the IgLON family of cell adhesion molecules (CAMs), which play essential roles in cell-cell communication and adhesion. OPCML was initially identified due to its ability to bind opioids, which suggested a potential role in the modulation of opioid signaling. However, subsequent research has revealed that its primary function lies in cell adhesion and tumor suppression.

OPCML is encoded by the OPCML gene located on chromosome 11q25. This gene is highly conserved across species, indicating its crucial role in cellular processes. OPCML is ubiquitously expressed in various tissues, including the brain, where it participates in neural cell adhesion and signaling. In recent years, OPCML has gained attention due to its tumor suppressor functions and its involvement in several cancers.

Protein Structure

The OPCML protein consists of several key domains that contribute to its function:

1. Extracellular Domain: OPCML has three immunoglobulin-like (Ig-like) domains in its extracellular region, which are critical for its role in cell adhesion and interaction with other molecules.
2. Transmembrane Domain: A single transmembrane domain anchors OPCML to the cell membrane, facilitating its role in cellular signaling and adhesion.
3. Intracellular Domain: The intracellular domain of OPCML is relatively short but plays a role in transmitting signals from the extracellular environment to the intracellular machinery.

The Ig-like domains are characteristic of the IgLON family and are involved in homophilic and heterophilic interactions, which are essential for cell adhesion and communication.

Classification and Subtypes

OPCML belongs to the IgLON family, which includes other members such as LSAMP (limbic system-associated membrane protein), NEGR1 (neuronal growth regulator 1), and IGLON5. These proteins share structural similarities, particularly the presence of Ig-like domains, and they participate in cell adhesion and neural development.

Function and Biological Significance

OPCML functions primarily as a cell adhesion molecule, playing critical roles in the following processes:

1. Cell-Cell Adhesion: OPCML facilitates adhesion between cells, which is essential for maintaining tissue architecture and cellular communication.
2. Neural Development: In the nervous system, OPCML is involved in the development and maintenance of neural networks, influencing processes such as synaptogenesis and axon guidance.
3. Tumor Suppression: OPCML has been identified as a tumor suppressor. It exerts its effects by interacting with various oncogenic proteins, inhibiting their activity, and promoting cell adhesion, which can counteract the invasive properties of cancer cells.

Clinical Issues

1. Cancer: OPCML is frequently downregulated or silenced in various cancers, including ovarian, gastric, breast, and lung cancers. The loss of OPCML expression is often due to hypermethylation of its promoter region. This silencing contributes to tumorigenesis by disrupting cell adhesion and enabling uncontrolled cell proliferation and invasion. Studies have shown that restoring OPCML expression can inhibit tumor growth and enhance the efficacy of chemotherapeutic agents.
2. Neurological Disorders: Given its role in neural development and cell adhesion, OPCML is implicated in certain neurological conditions. Altered expression of OPCML has been observed in disorders such as schizophrenia and autism, although the exact mechanisms and consequences of these changes are still being investigated.

Summary

Opioid binding protein/cell adhesion molecule-like (OPCML) is a critical member of the IgLON family of cell adhesion molecules. It plays essential roles in cell-cell adhesion, neural development, and tumor suppression. The protein's structure, characterized by three Ig-like domains, a transmembrane domain, and a short intracellular domain, is key to its function in cellular processes. Clinically, OPCML is significant due to its tumor suppressor functions and its involvement in various cancers, where its downregulation contributes to tumorigenesis. Additionally, OPCML's role in neural development implicates it in several neurological disorders. Ongoing research into OPCML aims to further elucidate its functions and therapeutic potential in cancer and neurological diseases.