Generating capture probes for spatial analysis
The present disclosure relates to compositions and methods for generating capture probes on a substrate for identifying the location of analytes in a biological sample.
1. A method of generating a spatial array comprising:
(a) providing a substrate comprising a plurality of acceptor oligonucleotides, wherein an acceptor oligonucleotide of the plurality of acceptor oligonucleotides comprises a spatial barcode, a first ligation handle, and a photocleavable protective group, wherein the acceptor oligonucleotide comprises a 3′ end comprising the photocleavable protective group, and the acceptor oligonucleotide comprises a 5′ end that is attached to the substrate;
(b) providing a single-stranded splint oligonucleotide comprising a nucleic acid sequence substantially complementary to the first ligation handle and a nucleic acid sequence substantially complementary to a second ligation handle;
(c) providing a plurality of donor oligonucleotides, wherein a donor oligonucleotide of the plurality of donor oligonucleotides comprises the second ligation handle and a capture domain;
(d) hybridizing the single-stranded splint oligonucleotide to the first ligation handle and the second ligation handle;
(e) releasing the photocleavable protective group from the 3′ end of the acceptor oligonucleotide; and
(f) ligating the acceptor oligonucleotide to the donor oligonucleotide, thereby generating a spatial array.
2. The method of claim 1 , wherein the donor oligonucleotide further comprises a functional sequence, a donor spatial barcode, a unique molecular identifier, or a combination thereof.
3. The method of claim 1 , wherein the acceptor oligonucleotide further comprises a cleavage domain, a unique molecular identifier, a functional sequence, or a combination thereof.
4. The method of claim 1 , wherein the capture domain comprises a poly(T) sequence.
5. The method of claim 1 , wherein the capture domain is a non-homopolymeric sequence.
6. The method of claim 1 , wherein the method further comprises contacting a biological sample to the generated spatial array.
7. The method of claim 6 , further comprising permeabilizing the biological sample after contacting the biological sample with the generated spatial array to allow an analyte in the biological sample to interact with the capture domain.
8. The method of claim 7 , wherein the analyte hybridizes to the capture domain.
9. The method of claim 7 , wherein the analyte is ligated to the capture domain.
10. The method of claim 7 , wherein analyte comprises DNA or RNA.
11. The method of claim 7 , wherein the method further comprises migrating the analyte in the biological sample to the capture probe.
12. The method of claim 11 , wherein the migrating comprises passive migration.
13. The method of claim 11 , wherein the migrating comprises active migration.
14. The method of claim 6 , wherein the method further comprises imaging the biological sample.
15. The method of claim 6 , wherein the method further comprises staining the biological sample.
16. The method of claim 15 , wherein the staining comprises hematoxylin and eosin (H&E) staining.
17. The method of claim 1 , wherein the ligating in (f) comprises enzymatic ligation or chemical ligation.
18. The method of claim 17 , wherein the enzymatic ligation comprises the use of a ligase selected from SplintR ligase, T4 DNA ligase, App ligase, and RNA ligase.
19. The method of claim 1 , wherein the single-stranded splint oligonucleotide comprises DNA, RNA, or a combination thereof.
20. The method of claim 1 , wherein the photocleavable protective group is released by exposing the acceptor oligonucleotide to light.
21. The method of claim 1 , wherein, prior to the releasing in (e), the photocleavable protective group is protected by applying a photomask.
22. The method of claim 1 , wherein the substrate comprises two or more partitions and wherein a partition of the two or more partitions comprises a plurality of features.
23. The method of claim 22 , wherein the plurality of features comprises a plurality of immobilized acceptor oligonucleotides.
24. The method of claim 23 , wherein an immobilized acceptor oligonucleotide of the plurality of immobilized acceptor oligonucleotides within the partition comprises a spatial barcode that is different from immobilized acceptor oligonucleotides in other partitions.
25. The method of claim 24 , wherein the plurality of donor oligonucleotides is delivered to the partition, wherein the donor oligonucleotide of the plurality of donor oligonucleotides further comprises a donor spatial barcode, wherein the donor spatial barcode comprises a different sequence compared to the spatial barcode of the immobilized acceptor oligonucleotides within the partition.
26. The method of claim 24 , wherein the two or more partitions are separated by physical barriers.
27. The method of claim 26 , wherein the physical barriers comprise walls or hydrophobic regions on the substrate.
28. The method of claim 25 , wherein the plurality of donor oligonucleotides is delivered using a microfluidic device.