Mathematics Colloquia and Seminars

Return to Colloquia & Seminar listing

Viruses are the only evolving organisms whose genomes are not double-stranded (ds) DNA. Indeed, many viruses have single-stranded (ss) RNA as their genomes. As a physical object, dsDNA is well-known to behave like a stiff, linear, polymer, essentially independent of its base-pair sequence, and the statistical physics describing its ensemble of configurations is well-understood. ssRNA, on the other hand, has a secondary structure that depends strongly on its nucleotide sequence. As I explain in my talk, RNA behaves accordingly like a flexible, effectively branched, polymer, whose statistical properties have not been well investigated, especially for molecules as long as viral genomes. Further, because of these fundamental differences in the phenotypes of DNA vs RNA genomes, the corresponding viral life cycles are necessarily very different. For example, DNA viruses are strongly pressurized, with genome packaging requiring a large amount of work, whereas RNA viruses can self-assemble spontaneously, enabling in vitro reconstitution from purified components of infectious virions and of gene delivery systems.

Faculty host: Javier Arsuaga Please contact Professor Arsuaga if you would like to meet with the speaker (jarsuaga@ucdavis.edu)