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Joined 2026-09-21 Message
Incoming links: J. Michael Li
Roger M. Wartell 2026-11-05
Roger M. Wartell is a biophysicist whose research connects nucleic-acid structure with physical measurements of folding and association. His Georgia Tech profile traces his training through physics degrees at Stevens and Rochester and identifies research on DNA melting, RNA-binding proteins and small RNA molecules in ice.[ref]
Roger Wartell profile at Georgia Tech. Biographical summary and research interests; linked CV, education and fields of interest
With Xueguang Sun and J. Michael Li, Wartell investigated a stable RNA hairpin that could form a metastable RNA dimer in frozen solution. Their study combined gel electrophoresis, sedimentation equilibrium and temperature-dependent absorbance to distinguish structures and their interconversion.[ref]
The scientific issue is broader than the existence of two gel bands. A band's electrophoretic mobility depends on molecular shape and experimental conditions as well as size. Independent measurements of association and thermal response help test whether the bands represent two folds of one strand or complexes containing different numbers of strands. Wartell's work illustrates how complementary physical measurements can constrain an otherwise ambiguous structural interpretation.
Xueguang Sun 2026-11-05
Xueguang Sun studied the structure and RNA-binding properties of the bacterial protein Hfq. His Georgia Tech doctoral thesis, dated May2006, identifies Roger M. Wartell as his committee chair and documents structural analysis, binding experiments and studies of RNA association.[ref]
Characterization of E coli Hfq structure and its RNA binding properties by Xueguang Sun. Title and approval pages; chaptersII–IV
The thesis combines predicted protein structure with experiments probing RNA binding, including gel electrophoresis and fluorescence anisotropy. That combination tests a structural hypothesis against binding behavior rather than treating a predicted surface as sufficient evidence of its function.[ref]
Characterization of E coli Hfq structure and its RNA binding properties by Xueguang Sun. ChapterIII, sections on gel mobility shift, fluorescence anisotropy and mutant binding
Sun later coauthored the2007 frozen-solution study with J. Michael Li and Wartell, showing that a stable RNA hairpin could convert efficiently into a metastable RNA dimer under freezing conditions.[ref]
These projects connect molecular recognition with competing structures: a protein can present alternative binding surfaces, and an RNA strand can pair internally or associate with another strand. Experiments are needed to distinguish those possibilities; a sequence or a mobility band alone does not specify the resulting complex.