Molecular Signal Jump: Translational readthrough in AGO1 mRNA across stop codon

Genetic message encoded in a messenger RNA (mRNA) is decoded to synthesize proteins by a process called translation. Ribosomes, the central machinery in this process, read the mRNA sequence in three nucleotide units termed as codons. There are specific codons in the mRNA which signal the ribosomes to start and stop the process of translation. However, under certain conditions, ribosomes ignore the stop signal and continue the process of translation till they encounter the next stop codon. This process is termed as translational readthrough.

In this study we have demonstrated translational readthrough in mammalian AGO1 mRNA that encodes an argonaute protein. This protein plays an important role in the function of microRNAs, which regulate protein synthesis. Translational readthrough in AGO1 mRNA generates a novel type (isoform) of argonaute protein with an ability to inhibit the function of miRNAs. Thus, our work has identified a molecular inhibitor of microRNA pathway.

Reference :

Anumeha Singh, Lekha E Manjunath, Pradipta Kundu, Sarthak Sahoo, Arpan Das, Harikumar R Suma, Paul L Fox, Sandeep M Eswarappa. Let-7a-regulated translational readthrough of mammalian AGO1 generates a microRNA pathway inhibitor. EMBO J. 2019 Jul 22:e100727. doi: 10.15252/embj.2018100727.

Contact :

Dr. Sandeep M Eswarappa
Assistant Professor
Department of Biochemistry
E mail:
Phone: +91-80-22932881