It is established that interactions of proteins with RNA play a crucial role at regulating RNA fate. However, a recent work led by the Hentze lab at EMBL has discovered that the reverse relationship is also possible. In other words, proteins can be regulated by RNA. We refer to this phenomenon as ‘riboregulation’.
This study shows that the RNA vault 1-1 (vtRNA1-1) interacts and regulates the protein p62, which is a key component of the autophagy machinery. As its name suggests, autophagy is a process by which a cell ‘eats itself’ to recycle its unnecessary or dysfunctional components. Interaction of vtRNA1-1 with p62 inhibits autophagy and this regulatory circuit exists in both human and mouse cells.
Importantly, the amount of vtRNA1-1 inside a cell varies according to the cell’s nutritional status. When is deprived of amino acids, vtRNA1-1 is reduced to enhance autophagy that will refill the pool of amino acids from unnecessary proteins to cover the cell needs.
This study raises the question of how common ‘riboregulation’ is and which processes are controlled by RNA. We hope to find the answer to these important questions in the years to come.
The Small Non-coding Vault RNA1-1 Acts as a Riboregulator of Autophagy. Horos R, Büscher M, Kleinendorst R, Alleaume AM, Tarafder AK, Schwarzl T, Dziuba D, Tischer C, Zielonka EM, Adak A, Castello A, Huber W, Sachse C, Hentze MW. Cell. 2019 Feb 21;176(5):1054-1067.e12. doi: 10.1016/j.cell.2019.01.030. Epub 2019 Feb 14.PMID: 30773316