Methods for spatial analysis of proteins and related kits
View Patent ↗Provided herein are methods and compositions for spatial analysis of macromolecules (e.g., proteins, polypeptides, or peptides). In some embodiments, the methods are for analyzing a macromolecule or a plurality of macromolecules, (e.g., peptides, polypeptides, and proteins) including determining spatial information and sequencing the macromolecule. In some embodiments, the analysis employs barcoding and nucleic acid encoding of molecular recognition events, and/or detectable labels. Also provided are compositions, e.g., kits, containing components for performing the provided methods for analysis of the macromolecule.
1 . A method of analyzing a polypeptide, comprising:
(a) providing a spatial sample comprising a polypeptide at a spatial location in the spatial sample, wherein the polypeptide is associated with a nucleic acid recording tag comprising a nucleic acid localization tag, and wherein the nucleic acid recording tag and the nucleic acid localization tag are both a part of the same nucleic acid molecule;
(b) analyzing the nucleic acid localization tag in situ at the spatial location in the spatial sample using fluorescent imaging, a combinatorial hybridization-based approach and/or in situ sequencing to generate a localization sequence comprising information of the spatial location of the polypeptide in the spatial sample;
(c) performing a polypeptide analysis assay on the polypeptide associated with the nucleic acid recording tag to generate an extended nucleic acid recording tag from the nucleic acid recording tag, wherein the polypeptide analysis assay comprises:
(i) contacting the polypeptide with a binding agent, wherein the binding agent binds to the polypeptide, and wherein the binding agent comprises a nucleic acid coding tag with identifying information regarding the binding agent; and
(ii) transferring the identifying information regarding the binding agent from the nucleic acid coding tag to the nucleic acid recording tag by primer extension and/or ligation to generate the extended nucleic acid recording tag;
(d) determining a sequence of the extended nucleic acid recording tag associated with the polypeptide including the sequence of the nucleic acid localization tag, thereby obtaining epitope information, amino acid sequence information, post-translational modification information, or any combination thereof, regarding the polypeptide; and
(e) matching the sequence of the nucleic acid localization tag determined in step (d) with the localization sequence generated in step (b);
thereby associating the information regarding the polypeptide obtained in step (d) with the spatial location of the polypeptide in the spatial sample.
2 . The method of claim 1 , wherein the nucleic acid localization tag comprises a barcode or a unique molecular identifier (UMI).
3 . The method of claim 1 , wherein a plurality of polypeptides is provided in a region of the spatial sample, wherein each polypeptide of the plurality is associated with a nucleic acid recording tag comprising the same nucleic acid localization tag.
4 . The method of claim 1 , wherein the nucleic acid localization tag is transferred from a substrate to the nucleic acid recording tag in or before step (a).
5 . The method of claim 1 , further comprising releasing the polypeptide associated with the nucleic acid recording tag from the spatial sample prior to performing the polypeptide analysis assay.
6 . The method of claim 1 , further comprising in step (c) repeating one or more times:
(i) contacting the polypeptide with an additional binding agent capable of binding to the polypeptide, wherein the additional binding agent comprises a nucleic acid coding tag with identifying information regarding the additional binding agent; and
(ii) transferring the identifying information regarding the additional binding agent from the nucleic acid coding tag to the extended nucleic acid recording tag.
7 . The method of claim 1 , wherein the binding agent comprises a polypeptide.
8 . The method of claim 1 , wherein the binding agent binds to an N-terminal amino acid residue or a chemically modified N-terminal amino acid residue of the polypeptide, and wherein the N-terminal amino acid residue or the chemically modified N-terminal amino acid residue of the polypeptide is cleaved after transferring the identifying information from the nucleic acid coding tag to the nucleic acid recording tag.
9 . The method of claim 1 , wherein the spatial sample comprises a tissue sample.
10 . The method of claim 1 , wherein the localization sequence is circularized.
11 . The method of claim 1 , wherein generating the localization sequence comprises rolling circle amplification (RCA) of the nucleic acid localization tag.
12 . The method of claim 1 , wherein the localization sequence is generated using a microscope-based method.
13 . The method of claim 1 , wherein the localization sequence is generated by nucleic acid sequencing.
14 . The method of claim 1 , further comprising collecting the polypeptide with the nucleic acid recording tag comprising the nucleic acid localization tag prior to performing the polypeptide analysis assay on the polypeptide.
15 . The method of claim 9 , further comprising fixing, cross-linking, and/or permeabilizing the spatial sample, wherein the fixing, cross-linking, and/or permeabilizing the spatial sample is performed prior to step (a) or performed in step (a).
16 . The method of claim 14 , wherein the polypeptide is fragmented after step (b) and prior to step (c) to form polypeptide fragments.
17 . The method of claim 16 , further comprising coupling the polypeptide fragments associated with the nucleic acid recording tag to a solid support prior to performing the polypeptide analysis assay.
18 . The method of claim 1 , wherein a plurality of polypeptides from the spatial sample is analyzed, and a plurality of extended nucleic acid recording tags representing the plurality of polypeptides are sequenced in parallel in step (d).