IPXK1

IPXK1, also known as Isoleucyl-tRNA protein kinase 1, is an enzyme encoded by the IPYK1 gene in humans. This protein plays a crucial role in the cellular stress response, specifically in the regulation of protein synthesis. When cells experience stress, such as nutrient deprivation or exposure to toxins, IPXK1 becomes activated.

Upon activation, IPXK1 phosphorylates leucyl-tRNA synthetase (LARS1). This phosphorylation event leads to the inhibition of LARS1's enzymatic activity. LARS1 is essential for attaching the amino acid leucine to its corresponding transfer RNA (tRNA) molecule, a critical step in protein translation. By inhibiting LARS1, IPXK1 effectively slows down the overall rate of protein synthesis. This reduction in protein production conserves cellular resources and allows the cell to better cope with the stressful conditions.

The IPXK1 pathway is therefore a key component of the integrated stress response (ISR), a conserved cellular mechanism that aims to restore homeostasis. Dysregulation of IPXK1 has been implicated in various diseases, including cancer and neurodegenerative disorders, highlighting its importance in maintaining cellular health. Further research is ongoing to fully elucidate the complex roles of IPXK1 and its potential as a therapeutic target.