Ahmed E. Dhamad

15 Questions 108 Answers 0 Followers

Questions related from Ahmed E. Dhamad

How can miRNA expression be measured by qPCR?

Hello! We have recently initiated several projects focused on analyzing microRNA (miRNA) expression. Although there are numerous resources available on quantifying miRNA expression using qPCR, we...

02 August 2025 5,229 3 View

What is the lowest number of samples that must be sequenced to get reliable results of NGS?

To make a comparison between a local strain of bacteria (for example E. coli) with the standard one (NCBI) in terms of genetic content using next-generation sequencing (NGS), what is the lowest...

15 July 2023 4,338 8 View

What does it mean when you have less cells# in flow cytometry plot compared to a control group?

Hi! I have run flow cytometry for 3 different cell lines (black, blue, and red) which were stained with red dye (FL2) with a same event number (15,000 events). However, the cell number (count; Y...

17 October 2017 3,061 3 View

Is there any difference regard to a cell behavior after knock out a gene using different plasmids ?

CRISPR-Cas9 has been used to knock out a gene in breast cancer cell (MCF7) by using two different plasmids. One plasmid has a puromycin selection marker and another one has a GFP selection marker....

01 February 2017 2,413 2 View

Is there any ideas why the over expressed protein behaves differently than the endogenous protein?

I over-expressed HA tagged mammalian protein (27KD) in 3 different cell lines; however, I saw the over expressed protein (exogenous) behaves differently than the endogenous protein in the all cell...

11 October 2016 7,548 8 View

What is the best way to test several genes expressions using qPCR?

I would like to determine several gene expressions for 4 different samples using qPCR with SYBR Green. Is it possible to run all of them in one plate regard to primers Tm differences? Would run...

10 July 2016 4,326 3 View

What is the best tool or program to predict orientation of a protein in a cell membrane?

I am working on a protein that mainly localizes in a cell membrane and have its amino acid sequence. It will be really helpful if know my protein orientation through the cell membrane ( where do...

30 January 2015 4,290 3 View

Which are the amino-sequence cutting sites of bovine thrombin?

Hello, I am trying to cleavage my protein from GST-tag by using Thrombin with its site ( L-V-P-R-G-S) which is provided by plasmid. However, I am confused because I saw after running my protein...

10 November 2014 8,207 9 View

What is the reason for often using labeled lysine and arginine rather than amino acids in SILAC?

What is the reason behind using heavy lysine and arginine often in SILAC (Stable isotope labeling by amino acid in cell culture) not other amino acids? And why is it on carbon 6? Thanks

11 October 2014 3,084 1 View

Can anyone help with Fluorescence Resonance Energy Transfer (FRET)?

1- Is the Fluorescence Resonance Energy Transfer (FRET)in the yeast different from the once in mammalian cells? I so, what is the difference?2- Can I perform FRET to distinguish the interaction...

09 October 2014 881 5 View

Can I separate two proteins which have almost the same M.Wt. and isoelectric points of 7.1 and 7.75 using IEC?

I have two proteins which have almost the same M.Wt. They also have isoelectric points (7.1 and 7.75). Can I separate them with Ion exchange chromatography(IEC)? What is the PI range by which Ion...

08 October 2014 1,157 6 View

Does anyone perform S-Carboxymethylation of Cysteine for protein or peptide? I am looking for the protocol . Any help would be appreciated

I am looking for the S-Carboxymethylation of Cysteine protocol. I want to methylate my protein by using iodoacetic acid. If you have a procedure for that, please send my a copy or tell me where I...

19 September 2014 7,954 5 View

What is the best approach to measure the mRNA level of a specific protein in cancer cells (MCF7)?

I am looking for a good method to know the mRNA levels of specific gene before and after a treatment of MCF7 cells.

05 July 2014 5,898 9 View

Is it important to know how many passages of the cell line have passed?

I am working with MCF7 and 293T cells. Do I have to know the # of passages that they have passed? If yes, what is the maximum passage's number, in general to my cells?

21 May 2014 3,123 17 View

How can I get rid of a non-specific binding with GST- beads?

I am doing protein mapping to my interesting protein (chop it off for different domains, mix them with other GST- protein to do in vitro binding assay and then they are pulled down with GST-...

12 May 2014 9,901 7 View