Michael Weir, professor of biology, professor of integrative sciences, received a grant worth $491,599 from the National Institutes of Health in September. Weir will use the award to better understand how ribosomes — the machines that make proteins — choose sequences in mRNAs (messenger ribonucleic acids) to start protein translation.
“This is an ongoing challenge in biology and is of great importance for investigations of cell function,” Weir said.
Weir is testing the hypothesis that sequences downstream of the translation start codon of mRNAs can form transient base pairs with a conserved sequence in 18S ribosomal RNA (called the 530 loop). This ribosomal RNA sequence is part of the structure of the ribosome and is located in the ribosome entrance tunnel for mRNAs.
He proposes that the base pairing is like a car’s braking system that helps the ribosome pause at the start codon, and that the transient base pairing also helps the ribosome walk along the mRNA in three-nucleotide steps as it adds amino acids to the growing new protein chain.