Given below are some of the statements regarding toll signalling pathway in drosophila.

A. Dorsal protein is a transcription factor with homology to the Rel/nuclear factor kappa B (NFκB) family of vertebrate transcription factors, which are involved in regulation of gene expression in vertebrate immune responses.

B. Toll signalling pathway is also used in the adult fly in defense against infection.

C. In the Drosophila embryonic Toll pathway Dorsal is held inactive in the nucleus by the protein Cactus.

D. The ligand for Toll is a fragment of the protein Easter, which is generated in the ventral vitelline space by the protease Spatzle.

E. When Toll is activated by binding the Spätzle fragment, its cytoplasmic domain binds a complex of the adaptor proteins dMyD88 and Tube. Tube interacts with, and activates, the protein kinase Pelle.

F. Activation of Pelle leads to the dephosphorylation of Cactus. This releases Dorsal, which is then free to enter a nucleus.

Choose the most appropriate combination of correct statements:

#Question id: 4015

#Unit 3. Fundamental Processes

When polymerase bind to promoter, it spontaneously undergoes a transition to the open complex and initiates transcription. This gives a low level of constitutive expression called the basal level. The rate -limiting step in basal level transcription

#Question id: 4016

#Unit 3. Fundamental Processes

Activators that stimulate this kind of promoter work by triggering a conformational change in either RNA polymerase or DNA; that is, they interact with the stable closed complex and induce a conformational change that causes transition to the open complex. This mechanism is an example of

#Question id: 4017

#Unit 3. Fundamental Processes

Which of the following sequences of events occurs when E. coli are released from catabolite repression by transfer to low-glucose medium?

#Question id: 4018

#Unit 3. Fundamental Processes

How does binding of the lac repressor to the lac operator block transcription initiation?

#Question id: 4019

#Unit 3. Fundamental Processes

Which of the following proteins does not “footprint” the lac operon control region?

#Question id: 4020

#Unit 3. Fundamental Processes

You are studying the expression of the gene that appears to be under the control of three different transcription-control regions during mouse embryonic development. Which one of the following is the BEST method to use to determine when each of these regions are active in the developing mouse embryo?