PolyA signals

PolyA Signal This is the polyadenylation signal for attachment of the polyA tail to generate mature mRNA it is important for transcription termination. 

Polyadenylation occurs at the 3 end of the pre-mRNA. First, the pre-mRNA is cleaved when a specific sequence, AAUAAA, is present in the transcript. Cleavage of the pre-mRNA occurs about 20 or so nucleotides downstream (3 ) of the polyA signal sequence. RNA polymerase II continues on the template, sometimes for as long as... 

Another popular GM plant is Bt -cotton and others. Bt stands for Bacillus thuringiensis which is known to produce several toxins to kill some insects. A toxin is modified in its DNA sequence by introducing introns, polyA signals, promoters, and enhancers. The modified DNA is then incorporated into the gene of... 

Figure 1 Nucleotide sequence of cDNA clone C/GPDH20 and the predicted amino acid sequence. The underlined sequence represents the consensus of a polyA signal. The invariably conserved amino acid residues of the NAD binding domain are circled [5].

Gideon Polya ts an associate Professor of Biochemistry at La Trobe University. Metbour -AustraP. Hsr irchi> rgely concerned with plant signal trartsa on and plat- de mechat -.- ... 

Omori s power law (Eq. 11.8). In this case an AE event was induced by a previous one (Polya process). Hirata [1987] analyzed AE signals that occurred while an unconfined basalt specimen was held at a constant high stress (at about 85% of ultimate stress). Individual bursts of events were treated as mainshock-aftershock sequences. He observed in most cases a transition from obeying an exponential decay law (Eq. 11.7) to Omori s power law (Eq. 11.8). Lockner [1993] re-evaluated some of Hirata s results. 

Polya, G.M., Wang, B.H. Foo, L.Y. (1995). Inhibition of signal-regulated protein kinases by plant-derived hydrolysable tannins. Phytochemistry, 38, 307-314. 

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