Final answer:
Cloning vectors such as plasmids incorporate elements like a selective marker, multiple cloning site, and an origin of replication. They require a promoter sequence for mRNA production and make use of restriction endonucleases and DNA ligase for DNA insertion.
Step-by-step explanation:
The question asks about the characteristics of cloning vectors and sequences necessary for producing mRNA from a transgene. Three elements incorporated into a plasmid vector for efficient cloning include a selective marker like an antibiotic resistance gene, multiple cloning site (MCS), and origin of replication. Additionally, for the transgene to produce mRNA, a promoter sequence is required upstream of the transgene. A cloning vector also utilizes restriction endonucleases and DNA ligase for the insertion of the target DNA.
Scientists generate a cDNA library when they are interested in the coding sequences of an organism's genome, which represent the genes that are actually being expressed as mRNA and translated into proteins, rather than the entire genomic DNA content including non-coding regions. A genomic library can be generated using phages instead of plasmids which offers the advantage of being able to clone larger fragments of DNA. Lastly, it is important for a DNA probe to be labeled with a molecular beacon to enable detection and visualization during hybridization assays.