IRESite record type: plasmid_with_promoter_and_putative_IRES_without_translational_characterization
The shape of the nucleic acid molecule translated: linear
The quality of the mRNA/+RNA sequence: our_best_guess
The mRNA/+RNA description:
Putative in vivo bicistronic T7 transcript with CAT and GFP cistrons and 5'-UTR containing EMCV IRES
terminated by Tphi transcription terminator. The EMCV-R IRES is located between nucleotides 57-608 of the
putative mRNA and lacks the very rightmost 6 bases immediately preceding the initiator AUG codon of EMCV
polyprotein. A putative ERAV IRES is located in the intercistronic region with its second AUG mutated from
AUG to AUA and with GNRA motif converted to GNRG. The GNRA change completely abolished IRES activity.
The mRNA/+RNA sequence represented in the +DNA notation:
Credibility of mRNA sequence: end-to-end_sequence_reverse_engineered_and_should_match_experiment
The description of the protein encoded in this ORF: chloramphenicol acetyltransferase
The translational frameshift (ribosome slippage) involved: 0
The ribosome read-through involved: no
The alternative forms of this protein occur by the alternative initiation of translation: no
The ORF absolute position (the base range includes START and STOP codons or their equivalents): 615-1274
It appeared the ERAV 5'-UTR region downstream the poly(C) tract contains 5 AUG codons. The first 4 are in
pairs adjacent to each other, while the fifth is the most downstream and is alone. Three types of proteins
were detected from complete ERAV IRES 245-961, called Lab-GFP, Lb-GFP, GFP. The naming Lab and Lb reflects
the fact that possibly viral proteases Lab and Lb are initiated at those respective AUG codons.
In this particular construct the AUG2 was mutated to AUA and GNRA motif was changed to GNRG (Fig. 5B).