Methods, compositions, and kits for determining the location of multiple analytes in a biological sample
Provided herein are methods, compositions, and kits for the spatial analysis of target nucleic acids, or complements thereof, by their 5′ end.
1 . A method for determining a location of a first target nucleic acid and a second target nucleic acid in a biological sample, the method comprising:
(a) contacting the biological sample with:
(i) a first probe and a second probe, wherein the first probe and the second probe each comprise sequences that are substantially complementary to sequences of the first target nucleic acid, and wherein the second probe further comprises a first capture sequence that is complementary to all or a portion of a first capture domain; and
(ii) a first primer comprising a sequence that hybridizes to a complementary sequence in the second target nucleic acid, and a functional domain;
(b) hybridizing the first probe and the second probe to the first target nucleic acid;
(c) generating a ligation product by ligating the first probe to the second probe;
(d) hybridizing the first capture sequence of the ligation product to the first capture domain on an array, wherein the array comprises a first plurality of capture probes, wherein a first capture probe of the first plurality of capture probes comprises: a first spatial barcode and the first capture domain;
(e) hybridizing the first primer to the second target nucleic acid and extending the first primer using the second target nucleic acid as a template to generate an extension product;
(f) incorporating a polynucleotide sequence comprising at least three nucleotides to 3′ end of the extension product;
(g) hybridizing a second primer to the polynucleotide sequence of the extension product of step (f), wherein the second primer comprises a second capture sequence;
(h) extending the extension product of step (g) using the second primer as a template, thereby incorporating a complement of the second capture sequence into the extension product;
(i) hybridizing the complement of the second capture sequence of the extension product of (h) to a second capture domain on the array, wherein the array comprises a second plurality of capture probes, wherein a second capture probe of the second plurality of capture probes comprises: a second spatial barcode and the second capture domain;
(j) determining (i) the sequence of the first spatial barcode, or a complement thereof, and (ii) all or a portion of the sequence of the ligation product hybridized to the first capture domain, or a complement thereof, and using the determined sequences of (i) and (ii) to determine the location of the first target nucleic acid in the biological sample; and
(k) determining (iii) the sequence of the second spatial barcode, or a complement thereof, and (iv) all or a portion of the sequence of the extension product corresponding to a sequence of the second target nucleic acid, or a complement thereof, and using the determined sequences of (iii) and (iv) to determine the location of the second target nucleic acid in the biological sample.
2 . The method of claim 1 , wherein the biological sample is disposed on the array comprising the first plurality and the second plurality of capture probes.
3 . The method of claim 1 , wherein the biological sample is disposed on a first substrate, and wherein the array comprising the first plurality of capture probes and the second plurality of capture probes is disposed on a second substrate and wherein the method further comprises aligning the first substrate with the second substrate, such that at least a portion of the biological sample is aligned with at least a portion of the array.
4 . The method of claim 1 , wherein the hybridizing in steps (d) and/or (i) comprise active migration of the ligation product and/or the extension product to the array, and optionally, wherein the active migration comprises electrophoresis.
5 . The method of claim 1 , wherein the polynucleotide sequence in step (f) comprises a homopolynucleotide sequence, optionally 5′-CCC-3′; or wherein the polynucleotide sequence in step (f) comprises a heteropolynucleotide sequence, optionally 5′-CGC-3′.
6 . The method of claim 1 , wherein the first capture domain comprises a first fixed sequence, optionally poly(T), and the second capture domain comprises a second fixed sequence, optionally poly(T).
7 . The method of claim 1 , wherein the first primer comprises a random hexamer or a random decamer.
8 . The method claim 1 , wherein the first primer comprises a poly(T) sequence.
9 . The method claim 1 , wherein the first primer comprises a sequence substantially complementary to a sequence in the second target nucleic acid encoding a constant region of an antibody; or
wherein the first primer comprises a sequence substantially complementary to a sequence in the second target nucleic acid encoding a constant region of a B cell receptor; or
wherein the first primer comprises a sequence substantially complementary to a sequence in the second target nucleic acid encoding a constant region of a T cell receptor.
10 . The method of claim 1 , wherein the functional domain comprises a primer binding site or a sequencing specific site.
11 . The method of claim 1 , wherein the first target nucleic acid is mRNA.
12 . The method of claim 1 , wherein the second target nucleic acid is mRNA.
13 . The method of claim 1 , wherein the extending in step (e) comprises the use of a reverse transcriptase.
14 . The method of claim 1 , wherein incorporating the polynucleotide sequence to the 3′ end of the extension product in step (f) comprises the use of a terminal deoxynucleotidyl transferase or the use of a reverse transcriptase.
15 . The method of claim 1 , wherein the second primer comprises RNA.
16 . The method of claim 1 , wherein the method further comprises removing the second target nucleic acid or any other nucleic acid hybridized to the extension product before the complement of the second capture sequence of the extension product hybridizes to the second capture domain of the second capture probe and/or removing the first target nucleic acid, or any other nucleic acid hybridized to the ligation product, before the first capture sequence of the ligation product hybridizes to the first capture domain of the first capture probe; and
wherein the removing comprises the use of an RNase, optionally, wherein the RNase is RNase H, or heat.
17 . The method of claim 1 , wherein the method further comprises a step of extending the 3′ end of the extension product of step (i) using the second capture probe as a template, thereby generating an extended capture product; and/or extending the second capture probe using the extension product of step (i) as a template, thereby generating an extended second capture probe; and/or a step of extending 3′ end of the ligation product using the first capture probe as a template, thereby generating an extended ligation product; and/or extending the first capture probe using the ligation product as a template, thereby generating an extended first capture probe.
18 . The method of claim 1 , wherein the determining in step (j) and step (k) comprises sequencing.
19 . The method of claim 1 , wherein the biological sample is a tissue section.
20 . The method of claim 19 , wherein the tissue section is a fixed tissue section, optionally, wherein the fixed tissue section is a formalin-fixed paraffin embedded tissue section, a paraformaldehyde-fixed tissue section, a methanol-fixed tissue section, or an acetone-fixed tissue section.
21 . The method of claim 1 , wherein the first probe and the second probe are substantially complementary to adjacent sequences of the first target nucleic acid.
22 . The method of claim 1 , wherein the first probe and the second probe hybridize to sequences that are not adjacent to each other on the first target nucleic acid and wherein the first probe is extended with a DNA polymerase, thereby (i) filling in a gap between the first probe and the second probe and (ii) generating an extended first probe.
23 . The method of claim 1 , wherein the first capture probe and/or the second capture probe further comprise one or more functional domains, a unique molecular identifier, a cleavage domain, or a combination thereof.
24 . The method of claim 1 , wherein the method further comprises fixing, staining, and/or imaging the biological sample.