Methods and products for expression of micro RNAs
The invention relates to microRNAs, methods of producing microRNAs and methods for using microRNAs.
1. A precursor microRNA molecule comprising:
an isolated nucleic acid comprising:
a stem-loop structure, wherein a microRNA sequence is incorporated into a stem of the stem-loop structure, and
a microRNA flanking sequence flanking at least one end of the stem-loop structure,
wherein the microRNA sequence and the microRNA flanking sequence are not derived from the same mircoRNA gene.
2. The precursor microRNA molecule of claim 1 , wherein the microRNA sequence is an artificial microRNA sequence.
3. The precursor microRNA molecule of claim 1 , wherein the precursor microRNA molecule includes at least two stem-loop structures.
4. The precursor microRNA molecule of claim 1 , wherein the microRNA flanking sequence is between 40 and 4,000 nucleotides in length.
5. The precursor microRNA molecule of claim 1 , wherein the precursor microRNA molecule has microRNA flanking sequences flanking each end of the stem-loop structure.
6. The precursor microRNA molecule of claim 1 , wherein the microRNA flanking sequence is between 40 and 2,000 nucleotides in length. derived from the same microRNA gene.
7. A vector for producing a precursor microRNA wherein the vector includes a sequence encoding a precursor microRNA of claim 1 , and at least one promoter element.
8. The vector of claim 7 , wherein the vector is a viral vector.
9. The vector of claim 8 , wherein the viral vector is a retroviral vector.
10. The vector of claim 7 , wherein the at least one of the promoter is an inducible promoter.
11. A host cell transfected with the vector of claim 7 .