A groundbreaking study reveals a hidden world of cellular communication, challenging our understanding of cell signaling regulation. But what does this mean for the future of medicine?
The RNA polymerase II enzyme, responsible for transcribing genes into messenger RNA, has long been a subject of interest. Its 'tail' undergoes phosphorylation, a process that guides gene transcription. Scientists from St. Jude Children's Research Hospital have delved deeper into this mechanism, uncovering a staggering 117 kinases capable of phosphorylating multiple sites on the tail. This discovery significantly expands our knowledge, as previously, only a limited number of kinases were known to play this role.
But here's where it gets intriguing: the study links this enzyme's activity to various diseases, including cancer. The cell-surface tyrosine kinase EGFR, for instance, was found to phosphorylate RNA polymerase II in the nucleus, and it's a well-known player in lung cancer. This finding suggests a direct connection between cell signaling and disease development.
The RNA polymerase II tail is a unique structure, composed of repeats of seven amino acids. Kinases attach phosphate groups to specific positions on this sequence, primarily at positions two and five. The role of the remaining five amino acids has been a topic of debate, until now.
Aseem Ansari, leading the St. Jude Department of Chemical Biology & Therapeutics, aimed to resolve this mystery. He acknowledged the existence of non-canonical kinases but emphasized the importance of proximity in determining specificity. The team's goal was to identify which kinases
