Question

A gene that a researcher wishes to clone into an expression vector uses a promoter that is already part of the vector. The gene will only transcribe correctly when in the same orientation as the promoter. How can the gene's orientation in the vector be assured?

Answer 1

The orientation of a gene in an expression vector is assured by aligning the gene in the same direction as the promoter. This can be determined by DNA sequencing or restriction enzyme analysis.

Step-by-step explanation:

The orientation of a gene in an expression vector can be assured by ensuring that the gene is inserted in the correct direction relative to the promoter. The promoter is the DNA sequence that initiates transcription and dictates which strand of DNA to copy. By aligning the gene in the same orientation as the promoter, the gene will transcribe correctly. The orientation can be determined by DNA sequencing or by using restriction enzymes to cut the vector and gene at specific sites. Example:If the promoter sequence in the vector is TATAAT and the gene is inserted in the 5'-3' direction, the promoter and gene will be in the same orientation.