Yang Zhang

12 Questions 5 Answers 0 Followers

Questions related from Yang Zhang

Proximity ligation assay to analyze protein interaction between endogenous and overexpressed proteins?

Hi All, I am analying the protein-protein interaction in an heterologous system by proximity ligation assay. I over-express one of the proteins, which is a cytosolic protein, and I am trying to...

30 April 2024 2,634 1 View

RT-PCR to analyze transcript levels?

Hi ALL, I am using a pair of primers to amplify a region in my gene of interest from cDNA samples. The cDNA samples are extracted from tissues of mouse of different ages. The gene is known to...

12 February 2024 3,612 4 View

Use HA synthetic peptide to elute 3x HA-tagged proteins off anti-HA resin?

Hi all: I am wondering if synthetic 1x HA peptide can efficiently elute 3X HA-tagged proteins off from anti-HA resin? I know that 1x FLAG peptide would not be able to efficiently elute 3x...

06 May 2021 1,272 0 View

How to do DNA normalization based on qPCR values?

Hi Everyone: I have a question regarding to qPCR. I am trying to do RT-PCR, and I want to have equal amount of input DNA for my RT-PCR, so I normalize my DNA input based on qPCR values of a...

01 February 2021 7,237 4 View

MS/MS protein analysis?

Hi Everyone: I want to quantify the relative amount of a protein in 2 samples. I will first digest the sample with trypsin, and subject the resulting peptides to LC-MS/MS analysis. I will then...

26 January 2021 8,587 3 View

How do I normalize RT-qPCR results?

Hi Everyone: I am studying a protein that is hypothesized to assist in transcription elongation. Its knockdown is expected to lead to decreased RNAPII processivity. I am trying to test this...

12 February 2020 568 4 View

DNA ethanoal precipitation contamination?

Hi all, I use Q5 NEB high-fidelity polymerase for PCR. I usually do 4 replicates, and ethanol precipitate the PCR products (0.1 sample volume 3 M NaAc, 2 sample volume of ethanol). I got a big...

28 September 2019 2,751 6 View

Protein treated with Calf intestinal phosphatase has increased mobility on gel. Does that indicate the protein is phosphorylated?

I have a protein of interest. Let's call it protein X. I treat the cell extract with calf intestinal phosphatase (from NEB). incubate at 37 degree for 1 h. Protein X would have increased mobility...

22 April 2019 7,962 3 View

Pol II CTD phosphorylation detection

Hi All, Pol II RPB1 CTD is phosphorylated, and can be detected as doublet bands on gel. I expressed a Myc tagged Rpb1 in cell, and tried to detect Rpb1-Myc. However, I can only see one band with...

01 January 1970 1,823 4 View

How to probe protein phosphorylation without an antibody?

Hi All, I have a protein of interest, X, and it has a single phosphorylation site identified. Another protein A might dephosphorylate X. I want to knock down A, and quantify the change of...

01 January 1970 9,700 7 View

Ramachandran plot outliers

Hi Everyone: When I analyze a protein crystal structure from the PDB using Ramachandran plot. It has some outliers, i.e. 10 or so. I would expect that all amino acid residues on a non-theoretical...

01 January 1970 8,410 3 View

How to show that two proteins are homologous?

Hi everyone: If I do protein alignment to two proteins, what percentage of identity between them would be required to consider them as homologous proteins? Is there any other parameters I need to...

01 January 1970 4,712 2 View