MicroRNAs in cellular transformation and tumorigenesis

MicroRNAs (miRNAs) are a novel class of small (approximately 23 nucleotides long), highly conserved, non-coding RNAs that function by broadly regulating gene expression. In animals, this regulation is achieved via interaction with target messenger RNAs (mRNAs), largely through their imperfect base pairing with the 3' untranslated regions (3' UTRs) of these target transcripts. Through this imperfect base pairing, miRNAs induce a repression of mRNA translation that is frequently coupled to enhanced turnover of the targeted transcript. This miRNA-mediated repression is highly related to that of RNA interference (RNAi), in which small non-coding RNAs exhibit perfect base pairing with target mRNA transcripts, leading to the endonucleolytic cleavage and degradation of these targeted mRNAs. Computational algorithms have been designed to predict putative miRNA binding sites within mRNAs. Using these predictions, it has been suggested that more than half of all mRNAs within mammals are under the control of miRNAs. Some of the earliest discovered miRNAs (characterized by genetic studies in the nematode Caenorhabditis elegans) were found to control the proliferation and differentiation of the cells in which they were expressed. As altered control of proliferation and differentiation frequently manifest in cancer in mammals, it was suggested that miRNAs might contribute to the development of tumorigenesis.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Biology.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Kumar, Madhu S. (Madhu Sudham)

Advisor dc:contributor.advisor

• Tyler Jacks.

• Biology.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/47879

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/47879