Embodiments disclosed herein provide for spatially tagged nuclei that are compatible with any genomic or multiomic single cell/nuclei assay to allow generation of a spatially resolved single cell sequencing library with single cell resolution.

Memory efficient methods determine corrected color values from image data acquired by a nucleic acid sequencer during a base calling cycle. Such methods may: (a) obtain an image of a substrate (e.g., a portion of a flow cell) including a plurality of sites where nucleic acid bases are read; (b) measure color values of the plurality of sites from the image of the substrate; (c) store the color values in a processor buffer of the sequencer's one or more processors; (d) retrieve partially phase-corrected color values of the plurality of sites, where the partially phase-corrected color values were stored in the sequencer's memory during an immediately preceding base calling cycle; (e) determine a prephasing correction; and (f) determine the corrected color values. In various implementations, these operations are all performed during a single base calling cycle. In certain embodiments, the methods additionally include using the corrected color values to make base calls for the plurality of sites. Sequencers may be designed or configured to implement such methods.

The invention relates to new methods for synthesising polynucleotide molecules according to a predefined nucleotide sequence. The invention also relates to methods for the assembly of synthetic polynucleotides following synthesis, as well as systems and kits for performing the synthesis and/or assembly methods.

The invention provides methods for synthesizing a product DNA molecule of any possible DNA sequence from a universal library of overlapping oligonucleotides. The method involves combining a plurality of the overlapping oligonucleotides in a reaction pool, where the sequences of the plurality of oligonucleotides comprise at least a sub-sequence of the product DNA molecule. The method also involves annealing the plurality of oligonucleotides, performing a ligation step, a selective digestion step, and an amplification step to thereby synthesize a sub-sequence of the product DNA molecule, and a produce DNA molecule using hierarchical assembly. The invention can be used to synthesize a DNA molecule of any possible sequence from the universal library, which can be accomplished through a hierarchal assembly scheme. In one embodiment the universal library comprises fewer than 10,000 pre-manufactured oligonucleotides that can be synthesized into the any possible DNA sequence. The product DNA molecule can be more than 150 base pairs long.

It has been established that one or more large double stranded DNA fragments (each 2,000 to 40,000 base pairs in size) can be captured and isolated from genomic DNA fragments using sequence specific PNA hybridization probes. Compositions and methods for enrichment of a multiplicity of long DNA sequences selected from the genome of any eukaryote are provided. Capture is performed using multiple PNA molecules with gamma-modified chiral backbones, comprising a mixture of neutral and positive chemical groups. Two or more PNA probes with covalently bound haptens, preferably biotin, target each DNA domain of interest for capture, isolation, and subsequent sequencing analysis of the multiplicity of enriched targets, including DNA methylation sequencing. The methods include enhancement of probe-DNA binding specificity through single strand binding proteins (SSB).

Provided herein are methods for generating circular nucleic acid molecules and circular nucleic acid libraries. The methods can be used to generate clonal populations of target nucleic acid molecules for downstream applications such as sequencing.

Methods of labeling or barcoding molecules within one or more portions of a plurality of cells are provided. Kits and systems for labeling or barcoding molecules within one or more portions of a plurality of cells are also provided. The methods, kits, and systems may utilize photo-controlled adapter sequences, nucleic acids tags, and/or linkers.

Provided are a rolling circle amplification method, a method for preparing a sequencing library, and a DNA nanoball prepared therefrom. The rolling circle amplification method includes: sequentially denaturing and annealing a double-stranded DNA and a mediating sequence in a same system, to complementarily pair the mediating sequence with two ends of a denatured single-stranded DNA; simultaneously introducing a ligase and a polymerase into the system to connect the two ends of the single-stranded DNA under action of the ligase; and performing a rolling circle amplification reaction under action of the polymerase by using the mediating sequence as a primer and the single-stranded DNA as a template, to obtain DNA nanoball.

The present invention relates to the technical field of molecular biology, and in particular, to a sgRNA sequencing linker and use thereof. The sgRNA sequencing 3 linker sequentially comprises the following sections from a 5-end to a 3-end: a first non-random section, a first random section, a second non-random section, a loop-forming DNA section, and a third non-random section, wherein the first non-random section is used for being linked to 3-end of the sgRNA; the first random section comprises 3 to 12 basic groups; the second non-random section is reversely complementary to the third non-random section so as to form a neck ring structure in conjuncture with the loop-forming DNA section; the third non-random section is used as a primer for sgRNA reverse transcription and replication; the loop-forming DNA section is composed of a first loop-forming section and a second loop-forming section from 5-end to the 3-end; the third non-random section and the second loop-forming section can be combined with the first sequencing linker primer sequence in a complementary pairing mode.

Provided herein are methods, compositions, and kits related to using a CpG binding protein. In one embodiment, the present disclosure includes methods, compositions, and kits related to using a CpG binding protein with a cytidine deaminase protein to identify methylated cytosine nucleotides. The cytidine deaminase can be an altered cytidine deaminase that includes an amino acid substitution mutation at a position functionally equivalent to (Tyr/Phe)130 in a wild-type APOBEC3A protein. In another embodiment, the present disclosure includes methods, compositions, and kits related to using a CpG binding protein with a ten-eleven translocase (TET) protein to identify methylated cytosine nucleotides.