Phototropism Is Mediated by the Lateral Redistribution of Auxin

In response to a directional light stimulus, the auxin produced at the tip, instead of being transported basipetally, is transported laterally toward the shaded side. Two flavoproteins, phototropins 1 and 2, are the photoreceptors for the blue-light signaling pathway that induces phototropic bending in Arabidopsis

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#Unit 3. Fundamental Processes

Readthrough transcripts refer to the fraction of transcripts that are not stopped by the terminator. (Readthrough is the same term used in translation to describe a ribosome’s suppression of termination codons.) 

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#Unit 3. Fundamental Processes

the termination event can be prevented by specific ancillary factors that interact with RNA and/or RNA polymerase, a situation referred to as antitermination.

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#Unit 3. Fundamental Processes

There are other parallels between initiation and termination. Both require breaking of hydrogen bonds (initial melting of DNA at initiation and RNA–DNA dissociation at termination), and both can utilize additional proteins (sigma factors, activators, repressors, and rho factor) that interact with the core enzyme.

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#Unit 3. Fundamental Processes

Initiation relies solely upon the interaction between RNA polymerase and duplex DNA, however, the termination event also involves recognition of signals in the transcript by RNA polymerase.

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#Unit 3. Fundamental Processes

Rho factor is an essential protein in E. coli that causes transcription termination.

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#Unit 3. Fundamental Processes

Initiation relies solely upon the interaction between RNA polymerase and duplex DNA, however, the termination event also involves recognition of signals in the transcript by RNA polymerase.