phot1 is the primary phototropic receptor mediates phototropism in response to low and high fluence rates of blue light. 

phot2 mediates phototropism in response to high light intensities

TLS Online TPP Program

#Id: 6657

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6658

#Unit 3. Fundamental Processes

In the nucleus, the cap is recognized and bound by the cap binding CBP20/80 heterodimer. This binding event stimulates splicing of the first intron and, via a direct interaction with the mRNA export machinery (TREX complex), facilitates mRNA export out of the nucleus. Once reaching the cytoplasm, a different set of proteins (eIF4F) binds the cap to initiate translation of the mRNA in the cytoplasm.

TLS Online TPP Program

#Id: 6659

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6660

#Unit 3. Fundamental Processes

The sequence AAUAAA is a signal for cleavage to generate a 3’ end of mRNA that is polyadenylated. Addition of poly(A) to nuclear RNA can be prevented by the analog 3’–deoxyadenosine known as cordycepin

TLS Online TPP Program

#Id: 6661

#Unit 3. Fundamental Processes

The site of cleavage/polyadenylation in most pre-mRNAs is flanked by two cis-acting signals:  An upstream AAUAAA motif, which is usually located 11 to 30 nucleotides from the site, and  A downstream U-rich or GU-rich element. 

he AAUAAA is needed for cleavage and polyadenylation because deletion or mutation of the AAUAAA hexamer prevents generation of the polyadenylated 3’ end

TLS Online TPP Program

#Id: 6662

#Unit 3. Fundamental Processes

Ser2 phosphatase Fcp1 regenerates RNA Pol II pool