ThNAC13, a NAC transcription factor from Tamarix hispida, confers salt and osmotic stress tolerance to transgenic Tamarix and Arabidopsis

作   者：王留强，李真，卢孟柱，王玉成
期刊名称：Frontiers in Plant Science
影响因子：4.298
卷 期 号：8
页     码：635
关键词： abiotic stress, NAC transcription factor, ROS-scavenging, stress resistance, Tamarix hispida
论文摘要：
NAC (NAM, ATAF1/2, and CUC2) proteins play critical roles in many plant biological
processes and environmental stress. However, NAC proteins from Tamarix hispida have
not been functionally characterized. Here, we studied a NAC gene from T. hispida,
ThNAC13, in response to salt and osmotic stresses. ThNAC13 is a nuclear protein
with a C-terminal transactivation domain. ThNAC13 can bind to NAC recognized sites
and calmodulin-binding NAC (CBNAC) binding element. Overexpression of ThNAC13 in
Arabidopsis improved seed germination rate and increased root growth and fresh weight
gain under salt or osmotic stress. Transgenic T. hispida plants transiently overexpressing
ThNAC13 and with RNAi-silenced ThNAC13 were generated for gain- and loss-offunction
experiments. Following exposure to salt or osmotic stress, overexpression
of ThNAC13 induced superoxide dismutase (SOD) and peroxidase (POD) activities,
chlorophyll and proline contents; decreased the reactive oxygen species (ROS) and
malondialdehyde levels; and reduced electrolyte leakage rates in both transgenic
Tamarix and Arabidopsis plants. In contrast, RNAi-silenced ThNAC13 showed the
opposite results in transgenic Tamarix. Furthermore, ThNAC13 induced the expression
of SODs and PODs in transgenic Arabidopsis. These results suggest that ThNAC13
improves salt and osmotic tolerance by enhancing the ROS-scavenging capability and
adjusting osmotic potential.