The abbreviated name of this ORF/gene: FLuc-fusion
The description of the protein encoded in this ORF: Firefly luciferase fused N-terminally with 6 extra aminoacid residues (including the initiator ATG) from BCL2
protein.
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: not tested
The ORF absolute position (the base range includes START and STOP codons or their equivalents): 2101-3771
Remarks:
Annotation of the plasmid: 16-812: CMV immediate early enhancer/promoter; 751: CMV transcription start;
869-1005: chimeric intron; 1049-1067: T7 RNA polymerase promoter (-17 - +2); 1066: T7 promoter transcription
start (+1); 1077-2012: RLUc; 2028-3165: BCL2 5'-UTR; 3166-4836: FFluc-fusion protein ORF
Authors corrections/comments: "We did utilize GI:179366 in numbering the bases for the BCL2 5'UTR. Due to the
high GC content at the 5'-end of this leader, the longest 5'-UTR we could obtain by RT-PCR was 1138bp in
length (Fig. 1). Unfortunately, the Methods/Materials was written earlier and the 1146bp was an estimate that
was later accidentally not corrected."
Negligible promoter activity was confirmed using promoter-less plasmid (IRESite Id:125) lacking
cytomegalovirus promoter with subsequent RLuc & FLuc luciferase activity detection (Fig. 3A, bottom panel).
Fig. 3B could be interpreted as either confirming cryptic promoter or aberrant splicing (which is proved in
Fig. 3C). pRL-BCL2-FL plasmid transcript is spliced into two forms, one of which is a monocistronic FLuc
transcript, making this plasmid unsuitable for DNA transfection studies.
The translation method used to study IRES function: in vitro
The in vitro translation system: rabbit reticulocytes lysate
The organism used for translation:
The temperature (in degrees of Celsia): 37
The relative translation efficiency in % of this IRES: 244.000
Name of IRES used as the positive control: HCV_type_1b
Name of the plasmid used as the positive control. pRL-HCV-FL-polyA
Name of the plasmid used as the negative control. pRL-FL-polyA
IRESite Id of the plasmid used as positive control. 112
IRESite Id of the plasmid used as negative control. 133
The relative translation efficiency in % of the positive control: 100.000
The relative translation efficiency in % of the negative control: 0
The size (length) of intercistronic region in the positive control: 485
The size (length) of intercistronic region in the negative control: 28
The effect of 5'-cap analogs on translation: not tested
Rapamycin affects translation: not tested
Type of RNA subject to translation: exogenous_RNA_with_GpppG_cap_with_polyA_tail
Remarks:
These data are based on Fig. 2 in the article. The measured values are hardly interpretable. In vitro
transcripts were produced using T7 polymerase in presence of m7G cap analog at ratio of 4:1 versus rGTP and
equimolar amounts of RNA were subject to translation in RRL. RNAs had short (35nt) polyA tail. pRL-FL was
used as the negative control although pRL-revH-FL would have been better. The actual expression from the
second cistron was 11% compared to the cap-dependent expression from the first cistron. The expression from
second cistron in positive control using HCV IRES had activity of 4.5% of the first cistron. Thus, the BCL2
IRES seemed to be more active then HCV IRES (about twice while in vivo experiments shown in Fig. 4 show the
opposite). The yields from the first cistron were not equal although all transcripts were capped and 5'-UTRs
had same length. One of the possible explanations might be that different efficiencies of capping account for
this. An empty vector pRL-FL-polyA was used as the negative control. pRL-HCV-FL-polyA was used as the positive
control.
The relative translation efficiency in % of this IRES: 6.000
Name of IRES used as the positive control: HCV_type_1b
Name of the plasmid used as the positive control. pRL-HCV-FL-polyA
Name of the plasmid used as the negative control. pRL-revHCV-FL-polyA
IRESite Id of the plasmid used as positive control. 112
IRESite Id of the plasmid used as negative control. 130
The relative translation efficiency in % of the positive control: 100.000
The relative translation efficiency in % of the negative control: 0.760
The size (length) of intercistronic region in the positive control: 485
The size (length) of intercistronic region in the negative control: 485
The effect of 5'-cap analogs on translation: not tested
Rapamycin affects translation: not tested
Type of RNA subject to translation: exogenous_RNA_with_GpppG_cap_with_polyA_tail
Remarks:
These data are based on Fig. 4A. In vitro transcripts were produced using T7 polymerase in presence of m7G cap
analog at ratio of 4:1 versus rGTP and equimolar amounts of RNA transfected into cells. RNAs had short (35nt)
polyA tail. Measured values were normalized to amount of radiolabelled mRNA transfected into cells.