Is polycistronic mRNA found only in prokaryotes?
Generally, Polycistronic mRNA is found in prokaryotes. This is different from eukaryotes that have monocistronic mRNA that only encodes for one protein product per mRNA molecule.
Is polycistronic mRNA found in eukaryotes?
However, polycistronic mRNAs are known to exist in eukaryotic viruses [5], hence the eukaryotic translational machinery must have ways to deal with them.
What does it mean if mRNA is Polycistronic?
The term polycistronic is used to describe an mRNA corresponding to multiple genes whose expression is also controlled by a single promoter and a single terminator. Polycistronic mRNAs are also called operons. All eukaryotic mRNAs are monocistronic.
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 the advantage of polycistronic mRNA?
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.
Do humans have lac operons?
Operons are common in bacteria, but they are rare in eukaryotes such as humans. In general, an operon will contain genes that function in the same process. For instance, a well-studied operon called the lac operon contains genes that encode proteins involved in uptake and metabolism of a particular sugar, lactose.
Is human mRNA Polycistronic?
This is the case for most of the eukaryotic mRNAs. Most of the mRNA found in bacteria and archaea is polycistronic, as is the human mitochondrial genome. Dicistronic or bicistronic mRNA encodes only two proteins.
What is the difference between Monocistronic and Polycistronic mRNA?
Polycistronic mRNA is a mRNA that encodes several proteins and is characteristic of many bacterial and chloroplast mRNAs. Polycistronic mRNAs consist of a leader sequence which precedes the first gene. Monocistronic mRNA is a mRNA that encodes only one protein and all eukaryotic mRNAs are monocistronic.
How does Polycistronic mRNA work?
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. Monocistronic mRNA is a mRNA that encodes only one protein and all eukaryotic mRNAs are monocistronic.