This project will investigate a novel aspect of stucture and function of the ribosome - the main molecular machine in the cell that makes new proteins. The ribosome itself contains several dozens of proteins, and it is only recently that these proteins were shown to be biochemically modified by methylation. Mutant yeast cells lacking those methylation enzymes usually show defects in ribosomal biosynthesis and altered sensitivity to antibiotics. The project will identify every enzyme that performs ribosome methylation reactions in yeast Saccharomyces cerevisiae and investigate the role these enzymes play in modifying ribosome activity. The project will train undergraduates and graduate students in scientific rigor and critical thinking prepare them as future researchers, teachers, mentors, and leaders in science policy.
This project will specifically investigate how the translational apparatus responsible for cellular protein synthesis is enhanced and regulated by modification of ribosomal and elongation factor proteins. It will focus on protein methylation reactions using baker's yeast (Saccharomyces cerevisiae), where powerful genetic tools are available. Mutant yeast cells lacking these enzymes display abnormal ribosomal biosynthesis, altered sensitivity to antibiotics, and defects in the fidelity of protein synthesis. Based on the initial success in identifying enzymes that modify cytoplasmic ribosomal proteins in yeast, as well as the effects of the loss of these enzymes, this research will determine how similar enzymes can work in mitochondrial ribosomes in yeast. The newly discovered process of protein histidine methylation in translation will also be studied. Finally, the role of protein methylation in the elongation factors that not only ensure that the correct aminoacyl-tRNA is matched to the mRNA codon but that guide the movement of free and peptidyl-tRNA will be investigated. The majority of the work will be conducted by undergraduate and graduate students. Senior graduate students mentor undergraduates as well as junior graduate students, under the direct supervision of the Principal Investigator. Another component of the broader impact of this work is continuing development and teaching of courses in the responsible conduct of research, including an intensive research integrity course for both undergraduates and graduates that stresses experimental design, data analysis and statistics, reagents authentication, and figure preparation.
