Figure 2.

Spatial correlation between the zones of transcript depletion and HSP70 induction. B–D were cut from the same PSbMV-infected cotyledon in the area shown in A; B and C are adjacent sections. Sections were subjected to in situ hybridization with probes for lox1:Ps:2 RNA (B), PsHSP71.2 RNA (C) and both probes together (D). The transcript depletion seen for lox1:Ps:2 appears to involve a rapid loss of transcript from the cytoplasm and the nucleus (B, Inset: compare the signal in the cytoplasm, c, and the nucleus, n, on the right and left of the panel, i.e., outside and inside the infection front, respectively). The zone of PsHSP71.2 induction corresponds with the first few cells of the zone of lox1:Ps:2 RNA depletion (B and C, arrows). When both probes are combined (D) the transcript-depleted zone gets correspondingly narrower. These data are summarized graphically (E).