Upstream sequence elements enhance poly(A) site efficiency of the C2 complement gene and are phylogenetically conserved.
Mapping transgene insertion sites reveals the α-Cre transgene expression in both developing retina and olfactory neurons | Communications Biology
Addgene: Hy_pMT EGFP SV40 pA Sequences
Frontiers | Enhanced Transgene Expression by Optimization of Poly A in Transfected CHO Cells
Regulatory elements in vectors containing the ctEF-1α first intron and double enhancers for an efficient recombinant protein expression system | Scientific Reports
Assembly of the cleavage and polyadenylation apparatus requires about 10 seconds in vivo and is faster for strong than for weak poly(A) sites. - Abstract - Europe PMC
The Poly(A) Signal, without the Assistance of Any Downstream Element, Directs RNA Polymerase II to Pause in Vivo and Then to Release Stochastically from the Template* - Journal of Biological Chemistry
Addgene: pDONR P2R-P3-SV40 polyA signal
Sequences 5' to the polyadenylation signal mediate differential poly(A) site use in hepatitis B viruses