MicroRNAs Dicer

Fig. 3 The microRNA (miRNA) pathway. An miRNA is first transcribed as part of an imperfect hairpin in a longer Pol II transcript with 5 cap (open circle) and polyadenosine tail (AAAAAA). The hairpin (pre-miRNA) is removed from the transcript by the nuclear RNase III type enzyme Drosha and its partner, DGCR8. Exportin-5 (Xpo-5) transports the resulting by-product to the cytoplasm, where Dicer liberates a short-lived miRNA duplex. The duplex is unwound, and one strand enters RISC. If the miRNA is mismatched to its target (left), it does not induce cleavage, but may inhibit translation. With a perfect or near-perfect match (right), the target RNA is destroyed by RISC.

Figure 27 The MicroRNAs Drosha and Dicer. (MiRNA. http //commons.wikimedia.org/wiki/ File MiRNA.svg by Kelvinsong http //commons.wikimedia.0rg/wiki/User Kelvmsong is licensed under CC BY 3.0 http //creativecommons.Org/licenses/by/3.0/deed.en) Reference Appendix 2, Explanations to the Figures...

MicroRNAs and Cancer. Atlas of Genetics and Cytogenetics in Oncology Haematology 2011 pp 1-27. The microRNAs Drosha Dicer miRNA http // commons.wiildmedia.org/wiki/File miRNA.svg hy Kelvinsong licensed under CC BY 3.0. 

Forstemann K, Horwich MD, Wee LM, Tomari Y, Zamore PD. Drosophila microRNAs are sorted into functionally distinct Aigonaute protein complexes after their production by Dicer-1. Cell. 2007 130 287-97. 

Chendrimada, T.P. et al. TRBP recruits the dicer complex to Ago2 for microRNA processing and gene silencing. Nature 436, 740-744, 2005. 

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