Physiological and transcriptional analyses reveal formation of memory
under recurring drought stresses in Gossypium hirsutum
Abstract
Drought, salinity, extreme temperatures, pathogens, and attacks by
herbivores are environmental stresses that plants experience repeatedly.
In order to survive in repeated stressful environments, plants have
evolved a new adaptive mechanism known as ‘stress memory’. Coordinated
responses of cell, gene/genome, and epigenetic modifications, including
altered physiological responses, gene activation, hyper-induction and
chromatin modification are considered necessary for the formation of
stressed memories. Cotton ( Gossypium spp.) is an important
economic crop, which can be used as raw materials in many fields and has
high economic value. Here, we ensured that G. hirsutum drought
memory was established after cycles of mild drought and re-watering
treatment, and studied gene expression by whole-transcriptome RNA
sequencing. The physiological, biochemical and molecular mechanisms of
drought stress memory formation in G. hirsutum were revealed. As
a histone modification, H3K4me3 plays an important role in [+/+]
transcript memory. In addition, the intergenerational inheritance
phenomenon of drought stress memory in G. hirsutum was also
exhibited. Our results showed that the pathways of long-term and
short-term memory may be different.