Doctor of Philosophy (PhD)
In S. cerevisiae, ribosomal protein L30e, in addition to being an integral part of the ribosome, autoregulates its levels of expression by: 1) binding to its transcript, inhibiting splicing; and 2) to its messenger RNA, inhibiting translation. This work explores ribosomal protein L30e binding to two short RNA fragments that mimic RNA-L30e binding sites. The L30e has a 100-fold higher affinity for its own transcript mRNA than for the helix 58 ribosomal rRNA target. Site-directed mutagenesis studies suggest that L30e maintains the same interaction network in both RNAs. Thermodynamics of L30e binding to RNAs give a direct insight into the energetic and entropic characteristics of complexes in aqueous solution and nicely complement the structural views derived from existing X-ray crystallography and multidimensional NMR studies. Experimental data support the scenario that in yeast L30e binds to an already pre-formed RNA helix 58.
Kokona, Bashkim. "The L30e ribosomal protein from S. cerevisiae binds to its transcript RNA more strongly than to its primary target helix 58 of ribosomal RNA." PhD Diss., Bryn Mawr College, 2018.