dc.contributor.advisor | Gu, Li-Qun | eng |
dc.contributor.author | Wang, Yong, 1980- | eng |
dc.date.issued | 2012 | eng |
dc.date.submitted | 2012 Spring | eng |
dc.description | Title from PDF of title page (University of Missouri--Columbia, viewed on May 15, 2013). | eng |
dc.description | The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. | eng |
dc.description | Dissertation advisor: Dr. Li-Qun (Andrew) Gu | eng |
dc.description | Includes bibliographical references. | eng |
dc.description | Vita. | eng |
dc.description | Ph. D. University of Missouri--Columbia 2012. | eng |
dc.description | "May 2012" | eng |
dc.description.abstract | MicroRNAs (miRNAs) are a class of short (~14-27 nucleotides) noncoding RNAs that regulate gene expression at the post-transcriptional level. Aberrant expression of miRNAs has been found in all types of tumors. Reverse transcription real-time polymerase chain reaction (qRT-PCR) and microarrays have been developed for detecting microRNA; however, these methods need labeling and amplification, and suffer from cross-hybridization, low selectivity and lack of valid internal controls. The development of nanopore sensors for microRNA detection is a new effort. One of the superior properties of nanopore is that the ion current in a nanometer-scaled pore structure is very sensitive to the presence, location and conformation of single target molecules occupying the ion pathway. Here we show that a nanopore sensor based on the alpha-hemolysin protein can selectively detect microRNAs at the single molecular level in the plasma samples of lung cancer patients without labeling and amplification of microRNAs. First, we uncovered a signature current pattern that can be used to electrically track the double-stranded DNA (dsDNA) unzipping process. With the signature signals, we can also distinguish the release of dsDNA without unzipping. Second, based on the electrical signatures we identified, we have designed a nanopore-based microRNA sensor for the direct and label-free detection of target microRNA in a fluctuating background, such as plasma RNA extracts from clinical samples. This sensor can quantify picomolar levels of cancer-associated microRNAs and can distinguish single-nucleotide differences between microRNA family members. This nanopore method can be a useful tool for quantitative studies of microRNAs, which are important for non-invasive screening and the early diagnosis of diseases such as cancer. | eng |
dc.description.bibref | Includes bibliographical references. | eng |
dc.format.extent | x, 105 pages | eng |
dc.identifier.oclc | 872568848 | eng |
dc.identifier.uri | https://doi.org/10.32469/10355/35199 | eng |
dc.identifier.uri | https://hdl.handle.net/10355/35199 | |
dc.language | English | eng |
dc.publisher | University of Missouri--Columbia | eng |
dc.relation.ispartofcommunity | University of Missouri--Columbia. Graduate School. Theses and Dissertations | eng |
dc.rights | OpenAccess. | eng |
dc.rights.license | This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License. | |
dc.source | Submitted by University of Missouri--Columbia Graduate School. | eng |
dc.subject | nanopore sensor | eng |
dc.subject | microRNA detection | eng |
dc.subject | diagnostic medicine | eng |
dc.title | Characterization [of] nucleic acids unwinding and exploring its application in miRNA detection in the nanopore | eng |
dc.type | Thesis | eng |
thesis.degree.discipline | Biological engineering (MU) | eng |
thesis.degree.grantor | University of Missouri--Columbia | eng |
thesis.degree.level | Doctoral | eng |
thesis.degree.name | Ph. D. | eng |