Introduction
The Extracellular signal-regulated kinases (ERK) pathway is one of the most important signal transduction systems in a cell. This pathway regulates a lot of the fundamental processes of the cell including cell growth control and also cell death. The ERK pathway’s basic structure includes a couple of phosphorylations. The pathway provides a channel for the passing of signals from receptor that is located on the cell surface to the DNA inside the cell nucleus.
The signal transduction process through the ERK pathway is a complex process. Initially, the signaling molecule, that is, the epidermal growth factor (EGF) usually binds itself to a receptor on the surface of the cell. This receptor is known as the epidermal growth factor receptor (EGFR). The receptor then tranduces this signals to adaptors which then activate the pathway proteins. There are several ERK pathway proteins, like the Raf and the MEK1/2, but the core one is the ERK. The ERK protein usually communicates by continuously adding short chain phosphate groups to neighboring proteins and this process continues until the DNA in the cell is transcribed into a protein and a change in the cell is produced, for example cell proliferation, differentiation or division.
Turning on and off of the ERK pathway occurs when subsequent proteins, are given short chain phosphate groups continuously. This continuous phosphorylation is usually done by two isoforms of the ERK protein, the ER-1 and the ERK-2. Two examples of proteins that are phosphorylated are threonine and tyrosine. If one of these proteins along the ERK pathway undergoes mutation, it remains in that position of on and off and lead to abnormal cellular growth which giving rise to cancer. Apart from this, any other defect within the pathway can also give rise to cancer.
References
The ERK Signal Transduction Pathway. (2013, August 28). Retrieved June 13, 2013, from http://www.rndsystems.com/mini_review_detail_objectname_MR04_ERKSignalTransduction.aspx
