Article Figures & Data
Figures
- FIG. 1.
Transcription profiles for AcMNPV ORF32 (vfgf) in Spodoptera frugiperda cells. Microarray data from Jiang et al. (6) (filled circles) and Iwanaga et al. (5) (open circles) are plotted against time after infection of Sf21 cells with Bac-PH-EGFP (an AcMNPV recombinant lacking polh) at a multiplicity of infection (MOI) of 10 and infection of Sf9 cells with AcMNPV E2 at the same MOI, respectively. Transcription levels (y axes) are represented using the authors' explicit or implicit tabular designations of “Log (normalized expression level)” (left axis, Jiang et al. [6]) and percent maximum level (right axis, Iwanaga et al. [5]). The dotted line near the bottom of the plot area superimposes on these array data my assessment of transcript levels for monocistronic 0.6-kb ORF32 mRNA, as depicted in the Northern blot autoradiograph shown in Fig. 2B of Detvisitsakun et al. (2) (Sf21 cells were infected with AcMNPV L1 at an MOI of 20). The downward slope of this line begins at 12 hpi, when the intensity of the 0.6-kb band is maximal, and ends at 48 hpi, the last sampling time point, reflecting the “slight decrease in transcription at 24 and 48 hpi” noted by Detvisitsakun et al.; its peak is linked to the 12-hpi datum point of Iwanaga et al. in the sense that little more than half of the combined Northern-analysis band intensities at 12 hpi (2) is judged to comprise monocistronic vfgf mRNA. Since my assertion in the text is that only this latter mRNA can yield vFGF polypeptide, the divergent trajectories of the dotted and solid lines from this time point onward contrast, impressionistically, the abundance of ORF32-containing polycistronic transcripts that cannot generate vFGF and the paucity of monocistronic transcripts that can.
