Presentation on theme: "Ribosome footprinting Not all RNAs encode proteins."— Presentation transcript:
Not all RNAs encode proteins
Entire paper was written with existing data (but the data was originally generated by authors)
mRNA Translation (main steps)
Note 3’UTRs Ribosome + mRNA Also note that coding regions are highly conserved by a conservation score CSF Codon substitution frequency
Yet, lincRNAs look more like translated regions and 5’UTRs based on translational efficiency (TE = ribosome/mRNA)
Known classical non-coding RNAs have high translational efficiency
Here are some examples of known ncRNAS with high Translational efficiency
Ribosome Release Score (RRS)
Cutoff on RRS and Translation Efficiency Provide Better Separation
RSS separates coding regions This is using open reading frames (ORFs) in each of these regions.
There are lincRNAs with high conservation and a high RSS score (do these code proteins?)
Why high TE for lincRNAs? Reasons the authors give: – Non-ribosomal contamination – Seductive hypothesis in the discussion: Translational machinery is always engaged with transcripts in the cytosol of the cell. “Pervasive” engagement of the ribosome with transcripts. – This can be co-opted by evolution to create new protein- coding genes.