Libraries of regulatory sequences, methods of making and using same
Methods and compositions for the identification, isolation and characterization of regulatory DNA sequences in a cell of interest are provided. In particular, libraries of regulatory sequences are provided, in which each member of the library comprises a polynucleotide comprising sequences from an accessible region of cellular chromatin.
1. A library comprising a plurality of polynucleotides, each polynucleotide of the library comprising a vector and an insert, wherein each of the insert sequences consist essentially of accessible regions of cellular chromatin, wherein there are at least two different insert sequences and further wherein the library is obtained according to the method of:
(a) contacting cellular chromatin with a probe, wherein reaction of the probe with cellular chromatin results in polynucleotide cleavage at accessible regions of cellular chromatin;
(b) deproteinizing the cleaved chromatin of step (a);
(c) digesting the deproteinized chromatin of step (b) with a nuclease to generate a collection of polynucleotide fragments; and
(d) selectively cloning polynucleotide fragments comprising one end generated by probe cleavage.
2. A library according to claim 1 , wherein each insert sequence consists of an accessible region of cellular chromatin.
3. The library of claim 1 , wherein the cellular chromatin is obtained from cells at a particular stage of development.
4. The library of claim 1 , wherein the cellular chromatin is obtained from cells of a particular tissue.
5. The library of claim 1 , wherein the cellular chromatin is obtained from diseased cells.
6. The library of claim 1 , wherein the cellular chromatin is obtained from infected cells.
7. The library of claim, 1 , wherein, in step (a), the probe is a nuclease.
8. The library of claim 7 , wherein the nuclease is a restriction enzyme.
9. The library of claim 8 , wherein the probe comprises a plurality of restriction enzymes.
10. The library of claim 1 , wherein, in step (c), the nuclease is a restriction enzyme.