Question

The linalool synthase protein (LinS) mediates the production pf linalool, a monoterpene that imparts a pleasant scent to lavender plants. A graduate student decided to overexpress the LinS gene in unscented rose plants in order to enhance flower scent. He decided to clone the coding sequence for the LinS gene in the PstI site of pBR322 A (a housekeeping vector; see map in lecture slides or text), transform the construct into Agrobacterium cells, and use an established Agrobacterium-mediated transformation protocol to transform rose plants (Roses are amenable to Agrobacterium-mediated transformation).

Assuming the student conducted all experiments well (no experimental errors):

1. Explain why this strategy is unlikely to work. (3 points)
2. Provide detail on the modifications the student needs to make to the pBRT322 A vector for this strategy to work. (7 points)

Answer 1

This strategy will not work as the pBR322 is a cloning vector, but not an expression vector. In cloning vector, the gene can be cloned but the product will not be produced as promoter for that particular gene is lacking. As Linalool synthase is a eukaryotic gene, pBR 322 is not express linalool synthase in it and thus the experiment will fail.

The modifications required are:

i. He have to take an expression vector in which the promoter will be inserted at proper location. In this vector, the gene of linalool synthase will be expressed and he will get linalool synthase.

ii. The substrate on which linalool synthase will act must be present in the host pant , so that linalool can be produced.