Poster abstracts

Poster number 18 submitted by Keshav Gc

Methyltransferase enzyme RsmC act as an RNA chaperone during bacterial ribosome biogenesis

Keshav GC (Department of Chemistry and Biochemistry, Kent State University), Prabesh Gyawali (Department of Physics, Kent State University), Man B Kshetri (Department of Chemistry and Biochemistry, Kent State University), Hamza Balci (Department of Physics, Kent State University), Sanjaya Abeysirigunawardena (Department of Chemistry and Biochemistry, Kent State University)

Abstract:
A ribosome is the ribonucleoprotein molecular machine that biosynthesizes proteins in all living cells. Biogenesis of ribosomes is crucial for the survival of all living organisms. The presence of various transacting factors including modification enzymes is important to synchronize various processes that happens during ribosome biogenesis. We have identified the ability of modification enzyme RsmC to function as an RNA chaperone protein during ribosome assembly in addition to its methyltransferase activity. The rate of helix 34 (h34) strand annealing is increased by 25-fold in the presence of RsmC. Furthermore, RsmC denatures non-native secondary structures observed in RsmC substrate strand and the protein also destabilizes the secondary structure of the substrate strand. Furthermore, smFRET experiments confirmed the annealing and chaperone activity of protein RsmC. Various mutant rRNAs were also used in this study to investigate the nature of various intermediates observed during RsmC-dependent h34 strand annealing. These observed chaperone activity of RsmC will facilitate the fast formation of 30S head domain during ribosome biogenesis.

Keywords: Ribosome biogenesis, RNA chaperone proteins, rRNA methyltransferase