Probes of RNA structure and methods for using the same
Methods for obtaining structural data from RNA in a sample, and RNA probes for performing the same, are provided. Methods of reversibly modifying RNA is a sample, in vitro or in vivo, and reversible probes for performing the same, are provided. The RNA probes may be SHAPE probes that include aryl or heteroaryl acyl imidazoles. The RNA probes may be reversible probes that include an aryl or heteroaryl ring substituted with a hydroxyl-reactive group and an azido-containing group. Also provided are methods of comparing in vitro and in vivo RNA structural data. Also provided are methods of diagnosing a cellular proliferative disease condition, e.g., by probing HOTAIR RNA. Aspects of the invention further include compositions, e.g., probes and kits, etc., that find use in methods of the invention.
1. A method for obtaining structural data from a RNA in a sample, the method comprising:
contacting the sample with a SHAPE probe to acylate one or more unconstrained nucleotides of the RNA to produce a 2′-acylated RNA, wherein the SHAPE probe is described by formula (II):
wherein:
A is selected from a phenyl, a pyridyl, a pyrrolyl, a furanyl, a thienyl, a thiazolyl, an imidazolyl, an oxazolyl, a pyrimidinyl, a pyrazinyl and a pyridazinyl ring;
R 1 is H or a lower alkyl;
R 2 is H or a lower alkyl; and
analyzing the 2′-acylated RNA to obtain structural data.
2. The method of claim 1 , wherein A is substituted with a detectable label or a bioorthogonal functional group.
3. The method of claim 1 , wherein the SHAPE probe is described by one of the following structures:
wherein:
Z 8 is O, S or NR 4 , wherein R 4 is H or a lower alkyl; and
R 1 is a lower alkyl.
4. The method of claim 3 , wherein R 1 is methyl.
5. The method of claim 3 , wherein R 1 is selected from one of the following groups:
wherein X is selected from —N 3 , hydroxyl, protected hydroxyl, protected thiol, amino and protected amino; and
R 5 is H or an alkyl group substituent.
6. The method of claim 5 , further comprising applying a stimulus to the sample to de-acylate the 2′-acylated RNA.
7. The method of claim 6 , wherein the stimulus is a photon, a deprotection reagent or an azido-reactive agent.
8. The method of claim 7 , wherein:
R 1 is —CH 2 —N 3 or —CH 2 CH 2 N 3 ; and
the stimulus is selected from an arylphosphine, an alkylphosphine, an arylalkylphosphine and a dithiol.
9. The method of claim 2 , wherein A is substituted with the bioorthogonal functional group and the method further comprises:
contacting the sample with a modifying reagent under conditions sufficient to conjugate the reagent to the bioorthogonal functional group of the A ring of a 2′-acylated RNA.
10. The method of claim 9 , wherein the modifying reagent is selected from a a detectable label reagent comprising a fluorophore or a peptide tag and a solid support.
11. The method of claim 1 , wherein the sample is a cell.
12. The method of claim 1 , wherein the sample is in vivo.
13. The method of claim 1 , wherein the sample is in vitro.
14. The method of claim 3 , wherein the SHAPE probe is described by one of the following structures:
wherein Z 8 is O.
15. The method of claim 13 , wherein the SHAPE probe is:
16. The method of claim 13 , wherein the SHAPE probe is: