(11/11) Dr. Sarah Woodson

Dr. Sarah Woodson

Johns Hopkins University
Department of Biophysics

Friday, November 11, 2022
12:00 Noon – Room 120 Meyerhoff Chemistry Building
HOST:  Dr. Deepak Koirala

“Co-transcriptional assembly of ribosomal RNA”

 

RNA and protein complexes begin to assemble as the RNA is being transcribed.  A major question is how the 5′ to 3′ direction of RNA synthesis changes its folding pathway and the recruitment of protein partners. Chemical footprinting and single molecule fluorescence assays showed that ribosomal RNA folds into variable structures during transcription. Improper folding of the newly made RNA delays the stable addition of ribosomal proteins. This delay can be overcome by the binding of other ribosomal proteins or by chaperones that improve rRNA folding. By contrast, variable folding of transcribes allows small non-coding RNAs base pair with complementary sites as soon as the site emerges from the elongating RNA polymerase. The results support a model in which ribosomal proteins bind stably after the RNA has an opportunity to form long-range interactions, whereas antisense RNAs capture new transcripts before they have a chance to fold.