Overexpression of MdNup62 reduces high-temperature
resistance
Because MdNup62 was induced by high temperature, we investigated
the high-temperature resistance function of MdNup62 .
OE-MdNup62 Arabidopsis lines were subjected to a high-temperature
(45°C) treatment (Figure 4a). Additionally, the survival rate of
transgenic Arabidopsis was significantly lower than that of WT (Figure
4b). We also performed a qRT-PCR analysis of A. thaliana HSPs
(AtHSP101 , AtHSP22-ER , AtHSP21.0 , andAtHSP70T-2 ) (Figure 4c). Their expression levels in transgenic
Arabidopsis were reduced under high-temperature conditions.
Consistently, after the heat treatment, the ROS accumulation in leaves
was clear greater in OE-MdNup62 lines compared with WT (Figure
5a). In addition, the malondialdehyde and
H2O2 levels were significantly greater
than in WT (Figure 5b, c). Moreover, the superoxide dismutase,
peroxidase, and catalase activities were lower in OE-MdNup62lines than in WT (Figure 5d–f). High-temperature resistance assays were
carried out in transgenic tomato plants (Figure 6a). As in transgenicA. thaliana , the survival rate of transgenic tomato was
significantly reduced compared with WT (Figure 6b). The presence of the
transgene in
OE-MdNup62lines was confirmed by genomic PCR, and qRT-PCR (Figure 6c,d). The
expression levels of HSPs (HSP101 , HSP22-ER ,HSP21.0 , and HSP70T-2 ) in transgenic tomato were
significantly reduced under high-temperature conditions compared with
under normal growth conditions (Figure 6e). These results indicate thatMdNup62 reduces plant high-temperature resistance.