Src (gene)

Src (gene)

File:Src gene.png

The structure of the Src gene

Src is a proto-oncogene that encodes a tyrosine kinase protein known as Src. It is located on chromosome 20 in humans and is highly conserved across species. The Src protein plays a crucial role in cell signaling pathways, regulating various cellular processes such as cell growth, differentiation, and migration.

Discovery

The Src gene was first discovered in the early 1970s by Dr. J. Michael Bishop and Dr. Harold E. Varmus. Their groundbreaking research on the Rous sarcoma virus (RSV) led to the identification of the Src gene as the viral oncogene responsible for the transformation of normal cells into cancer cells. This discovery revolutionized the field of oncology and provided valuable insights into the molecular mechanisms of cancer development.

Structure

The Src gene spans approximately 60 kilobases and consists of 28 exons. It encodes a protein of 536 amino acids, which is composed of several functional domains. These domains include an N-terminal myristoylation site, a unique domain, a Src homology 3 (SH3) domain, a Src homology 2 (SH2) domain, a tyrosine kinase domain, and a C-terminal regulatory tail.

Function

The Src protein is a non-receptor tyrosine kinase that is involved in multiple signaling pathways. It acts as a molecular switch, transmitting signals from cell surface receptors to the nucleus, thereby regulating gene expression and cellular behavior. Src kinase activity is tightly regulated by phosphorylation and dephosphorylation events, ensuring proper control of cellular processes.

The Src protein is known to interact with various proteins and participate in diverse cellular functions. It plays a crucial role in cell proliferation, survival, adhesion, and migration. Additionally, Src is involved in the regulation of cytoskeletal dynamics, which is essential for cell shape changes and cell movement.

Role in Cancer

Aberrant activation of the Src protein has been implicated in the development and progression of various types of cancer. Src can be activated by several mechanisms, including overexpression, gene amplification, and mutations. Once activated, Src promotes uncontrolled cell growth, invasion, and metastasis, contributing to tumor formation and progression.

Inhibition of Src kinase activity has emerged as a promising therapeutic strategy for cancer treatment. Several small molecule inhibitors targeting Src have been developed and tested in preclinical and clinical studies. These inhibitors have shown promising results in certain cancer types, highlighting the potential of Src as a therapeutic target.

Clinical Significance

The Src gene and its protein product have been extensively studied in the context of cancer biology. Abnormal activation of Src has been observed in various malignancies, including breast cancer, colorectal cancer, lung cancer, and pancreatic cancer. High levels of Src activity are often associated with poor prognosis and resistance to conventional therapies.

Targeting Src in cancer therapy holds great promise. Clinical trials evaluating Src inhibitors, either as monotherapy or in combination with other anticancer agents, are ongoing. These studies aim to determine the efficacy and safety of Src inhibitors in different cancer types and patient populations.

See Also

• Proto-oncogene
• Tyrosine kinase
• Cell signaling
• Oncogene
• Cancer biology