Expression of a heterologous protein in CHO cells and in an E. coli system produced proteins...
Expression of a heterologous protein in CHO cells and in an E. coli system produced proteins with the same molecular weight on SDS-PAGE. Subsequent in vitro bioactivity studies demonstrated high-level activity with the CHO cell-derived recombinant protein, but no bioactivity with the E. coli derived product. Explain this discrepancy, and propose an experiment to test your hypothesis
Homework Answers
With the same gene in different organisms same protein can be expressed. In order to make each new protein functional proper protein modifications are needed.
The protein modifications include addition of certain moieties or removal of certain sequences, glycosylation, phosphorylation etc.
The proteins that are derived from may not be getting glycosylated, where as the proteins from the eukaryotic cells like CHO cells can get glycosylated.
Glycosylation is one of the important modification, which is needed to make a naive protein functional. As prokaryotic derived proteins cannot get glycosylated, the same heterologous protein will be showing no activity.
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Expression of a heterologous protein in CHO cells and in an E.
coli system produced proteins...
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You performed a co-immunoprecipitation experiment to identify cellular proteins associated with protein X. For the experiment,...
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e stwc snct 2pts. Caci 1. In order to elute Con A from the affinity beads,...
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You are conducting an experiment identifying enhancers that regulate the expression of a gene that codifies...
You are conducting an experiment identifying enhancers that
regulate the expression of a gene that codifies for a protein that
participates in cell division. The gene is called Mitosis
Regulatory Protein A or MRPA. The complete DNA sequences
for the MRPA promoter and coding region have been
identified. However, it is unknown if MRPA has enhancers
regulating its transcription. To answer this question your lab
first produced a transgenic cell line where GFP has been inserted
as a reporter gene....
Why are proteins heat denatured prior to analysis in SDS-PAGE? Select all answers that apply. Denaturation of the protein is necessary so that proteins run proportionally to their size, based on the interaction of SDS with the unfolded protein. Heat is used to hydrolyze the peptide bonds of the protein. The heat step allows the proteins to unfold, enabling the protein chain to be coated with SDS molecules. Heat is used to hydrolyze disulfide bonds. QUESTION 2 1.5 points Saved...
You performed a co-immunoprecipitation experiment to identify cellular proteins associated with protein X. For the experiment, you used antibodies against protein X that were immobilized on beads. You incubated these beads with cell lysates from either wildtype cells or cells lacking the gene encoding protein Y. After washing and eluting the bound protein off the beads, you separated each bound and unbound fraction by SDS-PAGE. Finally, you performed immunoblotting using antibodies against either protein Y or protein Z. The results...
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regulate the expression of a gene that codifies for a protein that
participates in cell division. The gene is called Mitosis
Regulatory Protein A or MRPA. The complete DNA sequences
for the MRPA promoter and coding region have been
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regulating its transcription. To answer this question your lab
first produced a transgenic cell line where GFP has been inserted
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