Rho binds to a sequence within the transcript upstream of the site of termination. This sequence is called a rut site (an acronym for rho utilization). 

The rho factor then tracks along the RNA until it catches up to RNA polymerase. When the RNA polymerase reaches the termination site, rho first freezes the structure of the polymerase and then invades the exit channel to destabilize the enzyme, causing it to release the RNA.

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#Id: 6166

#Unit 12. Applied Biology

B. thuringiensis is a spore forming bacterium, which produces a crystal protein as parasporic inclusion in the vegetative cell containing the spore.

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#Id: 6167

#Unit 12. Applied Biology

The cry gene of B. thuringiensis produces a protein, which forms crystalline inclusions in the bacterial spores. These crystal proteins are responsible for the insecticidal activities of the bacterial strains.

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#Id: 6168

#Unit 12. Applied Biology

Cry proteins divided into four main groups or first ranks, viz., Cryl, Cry II, CryIII and CryIV, on the basis of their insecticidal activities.

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#Id: 6169

#Unit 12. Applied Biology

The commercial Bt–cotton available today contain genes from the isolate B-thuringiensis, ssp. that produces Cry I A(a), Cry I A(b), Cry I A(c), Cry IIA.

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#Id: 6170

#Unit 12. Applied Biology

The Cry proteins are solubilized in the alkaline environment of insect midgut and are then proteolytically processed to yield a toxic core fragment.

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#Id: 6171

#Unit 12. Applied Biology

The toxin fragments of Cry proteins have 3 domains: 

Domain, I functions in pore and ion channel formations, 

Domain II is involved in receptor recognition, 

Domain III binds the receptor and affects channel properties. The toxin fragments arc believed to bind to specific high-affinity receptors present in the brush border of midgut epithelial cells