Early growth response 2 and Egr3 are unique regulators in immune system.

The immune system is evolved to defend the body against pathogens and is composed of thousands of complicated and intertwined pathways, which are highly controlled by processes such as transcription and repression of cellular genes. Sometimes the immune system malfunctions and a break down in self-tolerance occurs. This lead to the inability to distinguish between self and non-self and cause attacks on host tissues, a condition also known as autoimmunity, which can result in chronic debilitating diseases. Early growth response genes are family of transcription factors comprising of four members, Egr1, Egr2, Egr3 and Egr4. All of which contain three cyc2-His2 zinc fingers. Initially, Egr2 function was identified in the regulation of peripheral nerve myelination, hindbrain segmentation. Egr3, on the other hand, is highly expressed in muscle spindle development. Egr2 and Egr3 are induced due to the antigen stimulation and this signaling is implemented through the B and T cell receptors in the adaptive immunity. T cell receptor signaling plays a key role in Egr 2 and 3 expressions via their interaction with NFAT molecules. Egr 2 and 3 play a crucial role in regulation of the immune system and their involvement in B and T cell activation, anergy induction and preventing the autoimmune disease has been investigated. The deficiency of these transcription factors has been associated to deficient Cbl-b expression, a resistant to anergy phenotype, and expression of effector and activated T cells.