Date of Award




Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Chemistry

Content Description

1 online resource (xi, 92 pages) : color illustrations.

Dissertation/Thesis Chair

Jia Sheng

Committee Members

Jia Sheng, Alexander Shekhtman, Mehmet Yigit, Zhang Wang, Ken Halvorsen


fluorescence, nucleic acids, structural study, RNA, Metal ions

Subject Categories

Biochemistry | Biophysics


It has been known that the template-directed RNA chemical replication reaction produces mixture of backbones containing both 3’-5’ and 2’-5’ linkages. This backbone heterogeneity has been a significant problem in studying the emergence of RNA World from the prebiotic chemistry. However, very recently, it is reported that FMN binding aptamer and a hammerhead ribozyme are still able to retain considerable functions in the presence of certain 2’-5’ linkages, indicating that RNA backbones may be quite flexible and this backbone heterogeneity problem may not be as severe as originally thought. This finding also brings two related important questions: First, how does RNA adjust the structures to accommodate these 2’-5’ linkages? Second, what might have been the molecular consequence and the potential evolutionary functions of these 2’-5’ linkages in the original stage of life? These two questions were discussed by systematically studying the structural and functional effects of 2’-5’ linkages in three different RNA systems including duplex, aptamer and ribozyme.