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Joined 2026-09-21 Message
Incoming links: Xueguang Sun
J. Michael Li 2026-11-05
J. Michael Li is a coauthor, with Xueguang Sun and Roger M. Wartell, of the2007 study of frozen-solution conversion between an RNA hairpin and a metastable RNA dimer. The paper identifies the authors with Georgia Tech's School of Biology and gives Li's byline in this form.[ref]
Conversion of stable RNA hairpin to a metastable dimer in frozen solution by Xueguang Sun and others. Title-page byline and affiliation
The study examined a79-nucleotide RNA with two bands in native gel electrophoresis but one in denaturing conditions. Sedimentation equilibrium supported monomer and dimer assignments. Experiments on shorter segments implicated the first21nucleotides in dimer formation.[ref]
Conversion of stable RNA hairpin to a metastable dimer in frozen solution by Xueguang Sun and others. Abstract and Results, monomer/dimer identification and21-nucleotide segment
A useful distinction follows: two native gel bands alone do not count the number of strands in each structure. Changing the folding state can change electrophoretic mobility without changing strand mass. Combining a mobility observation with an independent association measurement addresses that ambiguity, which is central to interpreting this contribution.
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.