Degree Date



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.