Why Polycistronic eukaryotic mRNAs Cannot work?
for typical eukaryotic transcripts the ribosome falls off of the mRNA and would not be able to reach the next gene. in order for a eukaryotic ribosome to translate a polycistronic mRNA, it needs something that provides a function similar to the shine-delgarno sequence found in prokaryotes.
What is the advantage of Polycistronic genes?
In bacteria, gene expression is structured in operons containing polycistronic mRNAs encoding multiple proteins. This has the clear advantage that expression of several proteins can be regulated synchronously using a single promoter and terminator.
Are polycistronic mRNA rare?
Which of the following is NOT a feature of eukaryotic gene expression?…Correct!
| A. | polycistronic mRNAs are very rare |
|---|---|
| D. | mRNA is often extensively modified before translation |
| E. | multiple copies of nuclear genes, and pseudogenes can occur |
What is Polycistronic condition?
Polycistronic mRNAs consist of a leader sequence which precedes the first gene. The gene is followed by an intercistronic region and then another gene. A trailer sequence follows the last gene in the mRNA. Examples of a polycistronic transcripts are found in the chloroplast.
Why does E coli have Polycistronic messages?
polycistronic messages allow the bacteria to regulate several functionally related genes at the same time D.
What is the difference between Monocistronic and Polycistronic?
The monocistronic transcription unit contains a structural gene coding for only one polypeptide (mostly in eukaryotic cells), whereas the polycistronic transcription unit contains structural genes coding for more than one polypeptides (mostly in prokaryotic cells).
Why is eukaryotic DNA Monocistronic?
Generally eukaryotes have Monocistronic mRNA. This is because each of these proteins A, B, and C are produced by different mRNA molecules that can each be regulated independently.
Are humans Polycistronic?
Among the few examples of human polycistronic genes recognized, the additional cistrons appear to allow for 1) co-expression of multiple subunits of a protein that is part of a complex; 2) co-expression of similarly functioning proteins under slightly different spatial or temporal patterns, 3) or co-production of novel …
Why is polycistronic mRNA useful?
One key characteristic of prokaryotic mRNAs is that they can be polycistronic. A polycistronic mRNA contains two or more cistrons, each of which can be translated to an individual protein independently. Consequently, more than one protein can be produced from the same polycistronic mRNA.
Do eukaryotes have Polycistronic genes?
Eukaryotic genes can code for short peptides. Polycistronic arrangements are possible in eukaryotes. Short ORFs in leader sequences of normal genes may code for bioactive peptides. A search for more polycistronic peptide genes poses new bioinformatic challenges.
