Chromatin profiling compositions and methods
Compositions and methods for single reaction and multiplexed profiling of histone modifications. Compositions include a binding domain and adaptor or a nucleosome binding conjugate comprising a binding domain conjugated to an adapter. Methods include analyzing a plurality of nucleosomes comprising (i) contacting a plurality of substrates comprising a binding domain and adaptor composition with a solution comprising the plurality of nucleosomes, wherein a nucleosome comprising a histone modification or DNA binding protein binds to the binding domain; (ii) ligating an adapter with the nucleic acid barcode to the target DNA of the nucleosome comprising the histone modification or DNA binding protein; (iii) introducing universal sequences for amplifying the target DNA; (iv) amplifying the barcoded target DNA; and (v) analyzing the amplified barcoded target DNA by sequencing.
1 . A method for analyzing a plurality of nucleosomes, the method comprising:
(i) contacting a composition with a solution comprising the plurality of nucleosomes, the composition comprising:
a substrate,
a binding domain coupled to the substrate, and
an adapter,
wherein the binding domain binds to a DNA binding protein or a nucleosome comprising a histone modification,
wherein the adapter comprises a nucleic acid barcode sequence unique to the histone modification or the DNA binding protein,
(ii) ligating the adapter comprising the nucleic acid barcode to a target DNA of the nucleosomes;
(iii) introducing universal sequences for amplifying the target DNA;
(iv) amplifying the barcoded target DNA to obtain amplified barcoded target DNA; and
(v) analyzing the amplified barcoded target DNA by sequencing.
2 . The method of claim 1 , wherein after step (ii), further comprising (iia) releasing the nucleosomes from the substrate by cleaving the ligated adapter; and (iib) repeating steps (i) through (iia) at least once before performing step (iii).
3 . The method of claim 2 , wherein the steps (i) through (iia) are performed using one or more different types of substrates each comprising a different binding domain and adapter comprising the nucleic acid barcode; and/or using a different binding domain and adapter each time the contacting through the releasing steps are repeated.
4 . The method of claim 2 , wherein the releasing step (iia) comprises cleavage of the ligated adapter at a restriction site, uracil, inosine, an 8-oxoG or a ribonucleoside of the adapter by an enzyme that is specific for these bases, optionally in the presence of a second enzyme that cleaves abasic sites.
5 . The method of claim 1 , wherein prior to step (ii) adding the adapter to the plurality of nucleosomes bound to the binding domain; wherein after step (ii), step (iia) releasing the nucleosomes from the binding domain by adding a buffer that disrupts the interaction between binding domain and nucleosome; and (iib) repeating the steps (i) through (iia) at least once before performing step (iii).
6 . The method of claim 5 , wherein ligating the adapter comprises use of a T4 DNA ligase, CircLigase, T3 DNA ligase, T7 DNA ligase, 9°N DNA Ligase, Taq DNA Ligase, or E. coli DNA ligase.
7 . The method of claim 5 , wherein the step of introducing the universal sequences comprises ligating to the adapter a partially double-stranded Y-shape adaptor or a partially double-stranded bell-shaped adapter.
8 . The method of claim 5 , wherein the releasing step (iia) comprises adding a buffer comprising a reducing agent, an enzyme that specifically digests antibodies, a synthetic modified histone peptide that acts as a competitive binder, a surfactant, an acidic buffer with a pH of 6.5 or below, or an alkaline buffer with a pH of 8.5 or above, about 0.3 M to about 2 M NaCl, or about 0.5 M to about 1 M NaCl.
9 . The method of claim 1 , wherein the binding domain comprises an antibody, a scFv, a Fab fragment, a light chain of an antibody (VL), a heavy chain of an antibody (VH), a variable fragment (Fv), a F(ab′)2 fragment, a diabody, a VHH domain, a nanobody, a bispecific antibody, a bivalent binding domain directed at two histone modifications, an aptamer, an engineered macromolecule scaffold, an engineered protein scaffold, or a selective covalent capture reagent; or wherein the binding domain comprises a histone modification reader protein, a writer protein, or an eraser protein.
10 . The method of claim 9 , wherein the writer protein is a histone acetyltransferase, a lysine methyltransferase, an arginine methyltransferase;
wherein the reader protein comprises a Methyl-CpG-binding domain (MBD), a bromodomain adjacent to the zinc finger proteins (BAZ) domain, a bromodomain (BRD), a malignant brain tumor (MBT) domain, a plant homeodomain finger (PHD) domain, a chromatin binding (chromo) domain, a proline-tryptophan-tryptophan-proline domain (PWWP) domain, a tryptophan-aspartic acid dipeptide repeat domain (WD40), or a tudor domain; and/or
wherein the eraser protein is a histone deacetylase, histone lysine demethylase, or a histone arginine demethylase.
11 . The method of claim 1 , wherein the binding domain comprises a catalytically inactive variant of a histone modification writer or eraser protein.
12 . The method of claim 1 , wherein the adapter comprises at least one universal sequence element in addition to the barcode; wherein the adapter comprises a unique molecular identifier in addition to the barcode; wherein the adapter comprises a spatial identifier sequence in addition to the barcode; wherein the adapter comprises uracil bases, inosine bases, 8-oxo-G bases, ribonucleosides, or a restriction sequence; wherein the adapter comprises a recognition sequence of a restriction enzyme, a 8-oxoguanine-DNA glycosylase, a uracil-DNA glycosylase (UDG), an endonuclease, or a ribonuclease; and/or wherein the adapter comprises a substrate anchoring moiety.
13 . The method of claim 12 , wherein the substrate anchoring moiety is biotin or desthiobiotin; or wherein the substrate anchoring moiety is trans-cyclooctene (TCO), methyl-tetrazine (mTET), Dibenzocyclooctyl (DBCO), an azido or an alkyne.
14 . The method of claim 1 , wherein the adapter is partially double-stranded forming a Y-shape, where the double-stranded portion is configured for ligation to the target nucleic acid and each single-stranded arm comprises universal sequences, a modification barcode, and a unique molecular identifier; and/or wherein the adapter is partially double-stranded forming a hairpin comprising a stem region that is configured for ligation to the target nucleic acid and a single stranded loop, wherein the single-stranded loop comprises universal sequences, a modification barcode and a unique molecular identifier.
15 . The method of claim 1 , wherein the histone modification is a methylation, citrullination, acetylation, ubiquitination, ADP ribosylation, deamination, proline isomerization, or sumoylation of lysine or arginine; and/or wherein the histone modification is phosphorylation of tyrosine, serine, or threonine.
16 . A method for analyzing a plurality of nucleosomes, the method comprising:
(i) contacting a solution comprising the plurality of nucleosomes with a composition comprising a nucleosome-binding conjugate comprising:
a binding domain, and
an adapter conjugated to the binding domain,
wherein the binding domain binds to a DNA binding protein or a nucleosome comprising a histone modification,
wherein the adapter comprises a nucleic acid barcode unique to the histone modification or the DNA binding protein,
(ii) ligating the adapter with the nucleic acid barcode of the nucleosome-binding conjugate to a target DNA of the nucleosomes comprising a histone modification or a DNA binding protein to produce barcoded target DNA in an environment wherein generation of off-target barcoded DNA is less than 20% of the barcoded target DNA;
(iii) introducing universal sequences for amplifying the target DNA;
(iv) amplifying the barcoded target DNA; and
(v) analyzing the amplified barcoded target DNA by sequencing.
17 . The method of claim 16 , comprising transferring the adapters of one or two nucleosome-binding conjugates to the same target DNA.
18 . The method of claim 16 , comprising limiting the off-target barcoding by performing the ligating step in a micromolar, nanomolar, picomolar, femtomolar, attomolar, or zeptomolar solution of nucleosome and nucleosome-binding conjugate.
19 . The method of claim 16 , wherein prior to step (i) immobilizing a plurality of nucleosomes on a substrate at a spacing wherein off-target barcoding is less than 20%; and/or prior to step (iii) cleaving the adapter such that a nucleic acid end is generated with the structure suitable for ligation to other adapters, wherein the immobilizing step through the cleaving step are repeated at least once.
20 . The method of claim 19 , comprising limiting off-target barcoding by immobilizing the nucleosomes on a substrate at a spacing distance of 50 nm or more.
21 . The method of claim 19 , wherein the method comprises cleaving the adapter at an uracil, an inosine, an 8-oxoG, or a ribonucleoside of the adapter by an enzyme that is specific for the uracil, the inosine, the 8-oxoG, or the ribonucleoside of the adapter; and/or wherein the method comprises cleaving the recognition sequence of an adapter using a restriction enzyme.
22 . The method of claim 19 , wherein the adapter comprises a recognition sequence of a restriction enzyme, 8-oxoguanine-DNA glycosylase, a uracil-DNA glycosylase (UDG), endonuclease, or a ribonuclease.
23 . The method of claim 19 , comprising using a different binding domain and adapter each time the contacting through the cleaving steps is repeated.
24 . A method for analyzing a plurality of nucleosomes, the method comprising:
(i) introducing a universal connector to a target DNA of the nucleosome;
(ii) contacting a solution comprising the plurality of nucleosomes with a composition comprising a plurality of nucleosome-binding conjugates each comprising:
a binding domain, and
an adapter conjugated to the binding domain;
wherein the binding domain binds to a DNA binding protein or a nucleosome comprising a histone modification, and
wherein the adapter comprises a nucleic acid barcode sequence unique to the histone modification or the DNA binding protein,
(iii) connecting the adapters by ligation to produce ligated adapters;
(iv) hybridizing the universal connector of the target DNA to a 3′end of the ligated adapters;
(v) copying the sequence of the ligated adapters to produce a copy of barcoded target DNA;
(vi) introducing universal nucleic acid sequences for amplifying the target DNA;
(vii) amplifying the barcoded nucleosome DNA, and
(viii) analyzing the barcoded target DNA by sequencing.
25 . The method claim 24 , wherein introducing the universal sequences comprises ligating a forward or reverse sequencing adapter to the barcode.
26 . The method of claim 24 , wherein the binding domain of the nucleosome-binding conjugate is linked to an internal position of the nucleic acid adapter.
27 . The method of claim 24 , comprising A-tailing the nucleosomes in step (i).
28 . The method of claim 24 , comprising ligating a universal connector sequence in step (i).
29 . The method of claim 24 , comprising connecting the adapters of the bound plurality of nucleosome-binding conjugates by double-stranded, single-stranded, or splint ligation.
30 . The methods of claim 24 , wherein the nucleosome is obtained as a cell free circulating nucleosome from the blood of a subject.