MEq/L

Overview

MERTK is a gene that encodes the protein MER proto-oncogene, tyrosine kinase, which is a member of the TAM receptor tyrosine kinase family. This family also includes AXL and TYRO3. MERTK plays a crucial role in the regulation of immune responses, clearance of apoptotic cells, and maintenance of tissue homeostasis.

Structure

The MERTK protein is a receptor tyrosine kinase that spans the cell membrane. It consists of an extracellular domain, a single transmembrane helix, and an intracellular tyrosine kinase domain. The extracellular domain is responsible for ligand binding, while the intracellular domain transduces signals into the cell.

Function

MERTK is involved in the phagocytosis of apoptotic cells, a process known as efferocytosis. It recognizes "eat-me" signals on the surface of dying cells, such as phosphatidylserine, through its ligands, which include Gas6 and Protein S. Upon ligand binding, MERTK undergoes autophosphorylation and activates downstream signaling pathways that promote cytoskeletal rearrangement and engulfment of apoptotic cells.

In the immune system, MERTK helps to maintain self-tolerance and prevent autoimmunity by clearing apoptotic cells and modulating inflammatory responses. It is expressed on macrophages, dendritic cells, and other immune cells.

Clinical Significance

Mutations in the MERTK gene have been associated with retinitis pigmentosa, a degenerative eye disease that leads to vision loss. MERTK dysfunction can result in impaired clearance of apoptotic cells in the retina, contributing to photoreceptor cell death.

MERTK is also implicated in cancer biology. Overexpression of MERTK has been observed in various cancers, including leukemia, melanoma, and non-small cell lung cancer. It is thought to promote tumor cell survival, proliferation, and metastasis. As a result, MERTK is being investigated as a potential therapeutic target in oncology.

Research and Therapeutic Targeting

Research into MERTK has led to the development of small molecule inhibitors and monoclonal antibodies aimed at blocking its activity. These therapeutic agents are being tested in preclinical and clinical studies for their efficacy in treating cancers and other diseases associated with MERTK dysregulation.

Also see

• AXL
• TYRO3
• Receptor tyrosine kinase
• Retinitis pigmentosa
• Efferocytosis

External links

• MERTK Gene - NCBI
• MERTK Protein - UniProt