Chemical mutagens can be divided into two groups:

those that are mutagenic to both replicating and nonreplicating DNA, such as the alkylating agents and nitrous acid; and 

those that are mutagenic only to replicating DNA, such as base analogs— purines and pyrimidines with structures similar to the normal bases in DNA.

TLS Online TPP Program

#Id: 6770

#Unit 3. Fundamental Processes

Upf1 is the first NMD protein to act, binding to the terminating ribosome—specifically to its release factor complex.

TLS Online TPP Program

#Id: 6771

#Unit 3. Fundamental Processes

nonstop-mediated decay rescues ribosomes that translate mRNAs that lack a stop codon. When an mRNA lacking a stop codon is translated, the ribosome translates through the poly-A tail This results 

TLS Online TPP Program

#Id: 6772

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6773

#Unit 3. Fundamental Processes

The cap binding CBP20/80 complex appears to directly bind to the mRNA export machinery (the TREX complex)

TLS Online TPP Program

#Id: 6774

#Unit 3. Fundamental Processes

(NXF1), (NXT1), SR proteins, RNA helicases, REF (RNA export factor), PABPN1 are important proteins required for mRNA transport.

TLS Online TPP Program

#Id: 6775

#Unit 3. Fundamental Processes

mRNP export from the nucleus into the cytoplasm is controlled by the phosphorylation and dephosphorylation of mRNP adapter proteins, REF, the NXF1/NXT1 mRNP exporter to mRNPs.