PRKRA : protein activator of interferon induced protein kinase EIF2AK2
Description
The PRKRA (protein activator of interferon induced protein kinase EIF2AK2) is a protein-coding gene located on chromosome 2.
The PRKRA gene provides instructions for making a protein called PACT. This protein plays a role in the cell's response to stress, such as exposure to viruses, damaging molecules called free radicals, or other toxic substances. When a cell is under stress, the PACT protein turns on (activates) another protein called PKR, which then turns off (inactivates) the eIF2 alpha (eIF2α) protein. Inactivation of eIF2α lowers protein production, which helps protect cells from damage. The signals triggered by PACT can ultimately lead to self-destruction (apoptosis) of the cell if it remains under stress. The signals sent by the PACT protein are also important for a process in the brain called synaptic plasticity. Synaptic plasticity is the ability of the connections between brain cells (synapses) to change and adapt over time in response to experience. This process is critical for learning and memory.
The PRKRA protein activates EIF2AK2/PKR even without the presence of double-stranded RNA (dsRNA), causing phosphorylation of EIF2S1/EFI2-alpha. This results in the suppression of protein synthesis and the initiation of apoptosis. PRKRA is essential for the production of siRNA by DICER1 and the subsequent silencing of genes through siRNA. However, it doesn't appear to be involved in the processing of pre-miRNA into miRNA by DICER1. PRKRA promotes the association of UBC9 and p53/TP53, leading to the sumoylation of p53/TP53 at 'Lys-386' and phosphorylation at 'Ser-392', ultimately enhancing p53/TP53's activity in a EIF2AK2/PKR-dependent manner.
PRKRA is also known as DYT16, HSD14, PACT, RAX.
