dc.contributor.advisor | Chekanova, Julia | eng |
dc.contributor.author | Wang, Hsiao-Lin V. | eng |
dc.date.issued | 2014 | eng |
dc.date.submitted | 2014 Fall | eng |
dc.description | Title from PDF of title page, viewed on January 14, 2016 | eng |
dc.description | Dissertation advisor: Julia Chekanova | eng |
dc.description | Vita | eng |
dc.description | Includes bibliographical references (pages 200-238) | eng |
dc.description | Thesis (Ph.D.)--School of Biological Sciences. University of Missouri--Kansas City, 2014 | eng |
dc.description.abstract | Expansion of high-throughput sequencing technology has increased our understanding
in the importance of pervasive transcription and the resulting indispensable molecules, noncoding
RNAs (ncRNAs). A significant effort has been made in determining the biological
relevance of ncRNAs, including the small RNAs (smRNAs) and long ncRNAs (lncRNAs).
Studies have shown that ncRNAs can have very important regulatory functions such as the
establishment and maintenance of the epigenetic architecture of eukaryotic genomes.
However, these studies have only revealed the surface of ncRNAs’ functions in cells.
Motivated by the previously “hidden” transcriptome regulated by the Arabidopsis
exosome, we examined the role of ncRNAs in regulation of gene expression in two plant
model systems, Arabidopsis and Brachypodium. We set out to investigate whether the
Arabidopsis exosome complex modulates gene expression through regulating ncRNAs,
including both smRNAs and lncRNAs. Thus, the role of Arabidopsis exosome complex in
regulating smRNA metabolism was extensively investigated and we revealed the differences
between Arabidopsis core exosome, yeast and human exosomes in modulating smRNAs. Although we have only begun to categorize the lncRNAs regulated by the Arabidopsis
exosome, our data so far has led to intriguing speculations, including the possible role of
exosome in transcriptional regulation via controlling lncRNAs. The challenges still remain,
including establishing the regulatory role of specific lncRNAs regulated by the exosome and
other factors at transcriptional or post-transcriptional levels in different cellular contexts, and
most importantly, how the interaction between these lncRNAs and the chromatin is mediated.
We also investigated the role of smRNAs in biotic and abiotic stress responses in
Brachypodium. We identified a group of endogenous, stress-induced small interfering RNAs,
sutr-siRNAs, and its novel mechanism in targeting cis elements involved in splice site
selection. This finding will stimulate research of smRNA mediated stress responses in
agricultural important crops. It also provides a framework for more suitable experimental
systems, such as the Drosophila and mammalian cell cultures, to further investigate the
associated mechanistic details of sutr-siRNAs.
In this dissertation, we revealed new insights and detailed molecular mechanisms of
the Arabidopsis exosome complex in regulation of gene expression, as well as provided a
novel regulatory mechanism of endogenous siRNAs by being involved in splicing. Although
many challenges still remain to fully determine the mechanistic details and biological
significance of plant ncRNAs, the work presented in this dissertation has added to our
understanding in regulation of gene expression through ncRNAs in plants. | eng |
dc.description.tableofcontents | Introduction -- The role of the arabidopsis exosome in SiRNA-independent silencing of heterochromatic loci -- Characterization of the sub-group of SmRNAs producing genomic loci affected by the defect in arabidopsis exosome complex- Stress-induced endogenous SiRNAs targeting regulatory intron sequences in brachypodium -- Conclusion and future directions -- Appendix I. List of associated publications -- Appendix II. curriculum vitae | eng |
dc.format.extent | xv, 239 pages | eng |
dc.identifier.uri | https://hdl.handle.net/10355/47954 | eng |
dc.subject.lcsh | Gene expression | eng |
dc.subject.lcsh | Arabidopsis | eng |
dc.subject.other | Dissertation -- University of Missouri--Kansas City -- Biology | eng |
dc.title | Regulation of Gene Expression by Non-coding RNAs in Arabidopsis and Brachypodium | eng |
dc.type | Thesis | eng |
thesis.degree.discipline | Molecular Biology and Biochemistry (UMKC) | eng |
thesis.degree.discipline | Cell Biology and Biophysics (UMKC) | eng |
thesis.degree.grantor | University of Missouri--Kansas City | eng |
thesis.degree.level | Doctoral | eng |
thesis.degree.name | Ph.D. | eng |