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The Center for Synthetic Regulatory Genomics (SyRGe)

www.thedarkmatterproject.org

Institute for Systems Genetics

NYU Langone Health

2026 GENOME WRITING WORKSHOP

What does my Big DNA do?:

readout strategies

Jack Atwater

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I have built and integrated my big DNA. Now what?

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I have built and integrated my big DNA. Now what?

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What sort of information do I want?

DNA

RNA

Protein

Example useful information

Chromatin features

Visualization

RNA quantification

Protein interactions

Visualization

Transcription dynamics

Protein quantification and/or localization

Protein interactions

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What sort of information do I want?

DNA

RNA

Protein

Example useful information

Chromatin features

Visualization

RNA quantification

Protein interactions

Visualization

Transcription dynamics

Protein quantification and/or localization

Protein interactions

Phenotype

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What sort of information do I want?

DNA

RNA

Protein

Example useful information

Chromatin features

Visualization

RNA quantification

Protein interactions

Visualization

Transcription dynamics

Protein quantification and/or localization

Protein interactions

Phenotype

Too context-dependent

for today’s discussion

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What sort of information do I want?

DNA

RNA

Protein

Example useful information

Chromatin features

Visualization

RNA quantification

Protein interactions

Visualization

Transcription dynamics

Protein quantification and/or localization

Protein interactions

Minimal requirement:

- Unique sequence features that

distinguish your genes and products from those in your cells

(eg., SNVs)

Nice-to-have:

  • Synthetic features that make readout easier

(eg., fluorescent reporters)

- Disadvantage: can alter the biology of your gene

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Your big DNA needs unique sequences!

Mouse gene X

chrX

My payload

Nucleus

Landing pad

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Your big DNA needs unique sequences!

chrX

Nucleus

Mouse gene X

My payload

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Your big DNA needs unique sequences!

allele 1

allele 2

chr6

Nucleus

chrX

My payload

endogenous alleles

Mouse gene X

Mouse gene X

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Your big DNA needs unique sequences!

allele 1

allele 2

chr6

Nucleus

chrX

My payload

endogenous alleles

Problem: no distinguishing sequences!

Mouse gene X

Mouse gene X

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Your big DNA needs unique sequences!

allele 1

allele 2

chr6

Nucleus

chrX

My payload

endogenous alleles

Solution 1: Use completely different sequences (eg., different species)

Human gene X

Mouse gene X

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Your big DNA needs unique sequences!

allele 1

allele 2

chr6

Nucleus

chrX

My payload

endogenous alleles

Mouse gene X

Mouse gene X

Solution 2: Design minimal sequence differences for readout of interest

Synonymous

variants

Can distinguish mRNA

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Your big DNA needs unique sequences!

allele 1

allele 2

chr6

Nucleus

chrX

My payload

endogenous alleles

Mouse gene X

Mouse gene X

Solution 3: Add synthetic reporters

Fluorescent reporter

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DNA readout (completely different sequences)

My payload

Bound proteins

Eg., ChIP-Seq

Histone modifications

Eg., ChIP-Seq

Accessibility

Eg., ATAC-Seq

Chromatin features:

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DNA readout (completely different sequences)

My payload

Visualization

Ex. FISH

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DNA readout (synthetic reporters)

My payload

Visualization

Ex. TetO array

TetR-GFP

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RNA readout (completely different sequences)

mRNA quantification

My payload

products

Endogenous

gene products

Simplest: RT-qPCR

Useful normalization!

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RNA readout (completely different sequences)

mRNA quantification

RNA-seq (bulk or single cell)

My payload

products

Endogenous

gene products

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RNA readout (completely different sequences)

mRNA quantification

RNA-seq (bulk or single cell)

Splice variant analysis

Long-read sequencing

My payload

products

Endogenous

gene products

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RNA readout (completely different sequences)

mRNA quantification

RNA-seq (bulk or single cell)

Splice variant analysis

Long-read sequencing

RNA visualization

Ex. FISH

My payload

products

Endogenous

gene products

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RNA readout (completely different sequences)

mRNA quantification

RNA-seq (bulk or single cell)

Splice variant analysis

Long-read sequencing

FISH

RNA visualization

My payload

products

Endogenous

gene products

Bound protein analysis

Ex. RIP-Seq

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RNA readout (minimal sequence difference)

mRNA quantification

My payload

products

Endogenous

gene products

Simplest: RT-qPCR

Useful normalization!

Other readouts difficult

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RNA readout (synthetic reporters)

pooled integration

BC1

BC2

BC3

BC4

BC5

TCAGTGCCAACG

Barcode (BC) =

unique sequence tag

Ex.

Pooled readout of transcript levels using engineered barcodes

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RNA readout (synthetic reporters)

pooled integration

amplify and sequence barcode regions from

mRNA and DNA

BC1

BC2

BC3

BC4

BC5

TCAGTGCCAACG

Barcode (BC) =

unique sequence tag

BC1

BC2

BC3

BC4

BC5

450

37

713

121

334

quantify mRNA barcode counts normalized against DNA counts

Ex.

...

Normalized counts:

Pooled readout of transcript levels using engineered barcodes

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RNA readout (synthetic reporters)

Transcription dynamics (eg., bursting)

MS2 hairpins

+ (potentially) all the other readouts

MCP-GFP

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Protein readout (completely different sequences)

My payload

products

Endogenous

gene products

Protein quantification and/or localization

Assays: western blot, ELISA, FACS, IF

Species-specific epitope

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Protein readout (completely different sequences)

My payload

products

Endogenous

gene products

Protein quantification and/or localization

Assays: western blot, ELISA, FACS, IF

Protein-Protein interactions

Protein-RNA or DNA interactions

RIP-Seq

ChIP-Seq

RNA

DNA

Co-IP mass-spec

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Protein readout (synthetic reporters)

Epitope tag

(Eg., HA, Myc, His)

My payload

products

Endogenous

gene products

Protein quantification and/or localization

Assays: western blot, ELISA, FACS, IF

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Protein readout (synthetic reporters)

Epitope tag

(Eg., HA, Myc, His)

My payload

products

Endogenous

gene products

Protein quantification and/or localization

Assays: western blot, ELISA, FACS, IF

Fluorescent protein

reporter

OR

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Protein readout (synthetic reporters)

Epitope tag

(Eg., HA, Myc, His)

My payload

products

Endogenous

gene products

Protein quantification and/or localization

Assays: western blot, ELISA, FACS, IF

Fluorescent protein

reporter

OR

Protein-Protein interactions

Co-IP mass-spec

Protein-RNA or DNA interactions

RIP-Seq

ChIP-Seq

RNA

DNA

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Readouts key points

DNA

RNA

Protein

Key points:

- Add unique sequence features that

enable readout!

- Unique sequence requirements are dependent on desired readout

- Synthetic reporters make readout very easy

BUT, they can alter the biology of your gene

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Q&A