Technical Support Articles

Should I fragment my chromatin using enzymatic digestion or sonication when performing ChIP?

Both enzymatic digestion and sonication work when performing ChIP for histones, transcription factors, and cofactors. However, we have found that enzymatic ChIP gives higher levels...

What is the recommended incubation time for PTMScan® HS enrichments?

The incubation time for PTM peptide enrichment has been empirically determined with an optimum time of ~2 hours. Incubation times greater than 2 hours show no increase in PTM-speci...

Why are two bands observed when using some of your NDRG1 antibodies?

Have the S6 Ribosomal Protein (54D2) Mouse mAb #2317 and S6 Ribosomal Protein (5G10) Rabbit mAb #2217 been tested by IP?

We have tested both the S6 Ribosomal Protein (54D2) Mouse mAb #2317 and the S6 Ribosomal Protein (5G10) Rabbit mAb #2217 for IP; however, both failed to meet our standards for IP r...

What is the percent cross-reactivity of Anti-mouse IgG, HRP-linked Antibody #7076 with rat and human IgG and IgM?

The percent cross-reactivity of Anti-mouse IgG, HRP-linked Antibody #7076 is 6% for rat IgG and <1.0% for rat IgM, human IgG, and human IgM. 

How do I validate the PTM sites identified in PTMScan® experiments?

The validation of PTM sites may be accomplished in several ways. Often, the site of interest may be seen in the context of more than one peptide due to alternative forms caused by ...

Are the -20C components within the CUT&RUN Assay Kit #86652 stable to use if they have been stored at 4C for a period of time?

Upon arrival of the kit to your facility, the components should be broken down and stored at their recommended temperatures. We have conducted stability tests for a few components ...

Is SignalStain® Boost IHC Detection Reagent (HRP, Rat) #72838 cross reactive with rat IgM?

The root material used to make SignalStain^® Boost IHC Detection Reagent (HRP, Rat) #72838 is goat anti-rat IgG. However, in various formats (biotinylated, etc.) this roo...

What residues are recognized in human insulin receptor β by your Phospho-IGF-I Receptor β (Tyr1135/1136)/Insulin Receptor β (Tyr1150/1151) (19H7) Rabbit mAb #3024?

Our Phospho-IGF-I Receptor β (Tyr1135/1136)/Insulin Receptor β (Tyr1150/1151) (19H7) Rabbit mAb #3024 recognizes Tyr1189/1190 in isoform 1 (Long) and Tyr1177/1178 in isoform 2 (Sho...

Can the Cell Fractionation Kit #9038 be used for frozen cell pellets?

We have had customers perform this assay using frozen cell pellets, prior to adding any fractionation buffer, and the subsequent fractionation worked fine. Once you start fracti...

Will any of your α-Synuclein antibodies detect α-Synuclein fibrils or oligomers?

Unfortunately, we have not performed experiments in-house to determine if any of our α-Synuclein antibodies can detect oligomers or fibrils of α-Synuclein. We have found a helpful ...

Can CUT&RUN enriched DNA be analyzed by qPCR, or do I have to do NGseq to analyze my data?

The DNA yield for my CUT&RUN experiment seems a bit low compared to what I was getting in my ChIP experiments. How can I improve the yield?

A ChIP experiment uses 4M cells per reaction while a CUT&RUN assay only uses 5K to 100K starting cells, so it is expected to see a lower DNA yield from a CUT&RUN assay than...

How long after the completion of staining can I wait to image my slides when performing a SignalStar™ Multiplex IHC assay?

For Imaging Round 1, the staining should show robust signal when imaged up to 8 hours post completion of staining. For Imaging Round 2, imaging should be performed as close to the ...

What is the percentage of SDS in the ChIP Sonication Nuclear Lysis Buffer #28778?

The ChIP Sonication Nuclear Lysis Buffer #28778 included in the SimpleChIP^® Sonication Cell and Nuclear Lysis Buffers #81804 contains 0.1% SDS.

How should I store my antibody?

Proper storage of your antibody may vary depending on the product's storage buffer and antibody conjugation. Therefore, please refer to the "Storage" section of the p...

Do you have any tips for using FACS-isolated cells in CUT&RUN experiments?

We have no specific tips for using FACS-isolated cells in CUT&RUN experiments. Like a cultured cell suspension, if your isolated cells are in less than 40ul PBS, you can move d...

Why does the material in my new vial of Echinomycin #51434 look different?

Echinomycin #51434 is lyophilized into the vial, and any difference in the appearance of the lyophilized echinomycin is due to a dry coating of the compound in the vial. When you a...

Are your siRNAs pools or single duplexes?

All of our siRNAs are single duplexes. We discontinued pools a number of years ago to avoid off-target effects.

What is the fewest number of cells I can use in a reaction with the CST CUT&Tag kit?

We have shown that our CUT&Tag Assay Kit #77552 works with as few as 5,000-10,000 cells for histone modifications and 20,000 cells for transcription factors and cofactors.

Are the Protein G Agarose Beads #37478 compatible with goat antibodies?

While we have not tested our Protein G Agarose Beads #37478 with goat antibodies in-house, goat IgG has a strong binding affinity to protein G. Therefore, our Protein G Agarose Bea...

Which Phospho-p44/42 MAPK (Erk1/2) (Thr202/Tyr204) antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) with human samples?

We have several monoclonal antibodies for detecting p44 and p42 MAPK when phosphorylated at Thr202 and Tyr204 of Erk1, or Thr185 and Tyr187 of Erk2, that are validated for IF-IC wi...

Can I use DNA affinity columns to purify CUT&RUN DNA for transcription factors?

We have several monoclonal antibodies for p44 and p42 mitogen-activated protein kinases (MAPKs), also referred to as Erk2 and Erk1, that are validated for IF-IC with human samples....

Does your CD44 (156-3C11) Mouse mAb #3570 recognize all variants of human CD44?

The CD44 gene encodes 20 exons. Alternative splicing gives rise to CD44s and multiple CD44 variants (CD44v). CD44s is encoded by constant exons 1-5, 16-18, and 20. The CD44 vari...

My items say to store at -20°c but they were shipped in an envelope. Is it ok to use?

Yes, it is safe to use these items. Since 2003, CST has been shipping antibodies at room temperature when possible to reduce waste from packing materials. All CST antibodies are st...

Can I separate nuclear and cytoskeletal proteins using your Cell Fractionation Kit #9038?

Unfortunately, separation of nuclear and cytoskeletal proteins is not possible using our Cell Fractionation Kit #9038. Because cytoskeletal proteins are involved in the stabilizati...

What is the best way to choose an antibody for my CUT&RUN assay if I cannot find a CUT&RUN validated antibody for my target protein?

When selecting an antibody for use in CUT&RUN, we recommend starting with a ChIP or ChIP-seq-validated antibody; however, we have found that not all ChIP-validated antibodie...

Do you have mouse-reactive antibodies available for SignalStar™ Multiplex IHC?

Can you enrich for more than one PTM in a PTMScan® sample?

Yes, the flow through from a PTMScan experiment can be saved and stored at -80C for future enrichments. We have performed 5 different PTM enrichments sequentially from one sample. ...