Life Sciences Commons^™

Application Of Single Particle Electron Microscopy To Native Lens Gap Junctions And Intrinsically Disordered Signaling Complexes, Janette Bernadette Myers

Dissertations and Theses

Gap junctions are a class of membrane proteins that facilitate cell-to-cell communication by forming channels that directly couple the cytoplasm of neighboring cells. The channels are composed of monomers called connexins. Humans express 21 connexin isoforms in a cell-type specific fashion, and each isoform has distinct mechanisms of permeation and regulation. Co-assembly of multiple isoforms into a single intercellular channel can change channel properties, such as conductance and selectivity to substrates (e.g., ions, metabolites and signaling molecules). However, the mechanistic basis for this functional diversity has remained poorly understood. This lack of mechanistic insight has been due in large part …

The Effect Of Dynamic Kinetic Selection On An Evolving Ribozyme Population, Patrick David Poletti

Dissertations and Theses

Dynamic Kinetic Selection (DKS) suggests that kinetic, rather than thermodynamic, stability will dictate the composition of a replicating population of biomolecules. Here, the results obtained from a series of five related reactions involving gradually increasing percentages of randomly-mutated substrate fragments to generate variants of full-length Azoarcus group I intron through an autocatalytic self-assembly reaction involving a series of recombination events, showed DKS as a driving factor in dictating the population composition of full-length product assembled from substrates that had fewer positions available to randomization.

In trying to elucidate a plausible scheme for the origins of complex biomolecules on the prebiotic …