Light Regulated Osa-miR169e Is Implicated during Priming under High Temperature Stress in Rice

Akhilesh Kumar Kushawaha,Ambreen Khan,Neeti Sanan-Mishra,Sudhir Kumar Sopory

doi:10.4236/ajps.2019.109118

Abstract

Plants face biotic and abiotic stresses during their entire life cycle, which leads to the loss in crop productivity. It has been shown that a relatively shorter exposure to heat stress, called priming, results in better adaptation of plants under subsequent stresses, which plants may face. While rice plants in nature often encounter high temperature stress conditions, the strategies to cope with those are poorly understood. We identified the involvement of microRNA pathways in the adaptation to heat stress (HS) at the physiological and molecular levels. It was observed that osa-miR169 levels are altered after HS and in response to light conditions. Its expression was also regulated by heat priming during anthesis and effectively responds to the successive exposure to high temperature stress during grain filling in rice. Osa-miR169 targets nuclear factor Y (NF-Y). We propose that osa-miR169: NF-Y regulatory module may be important for HS memory induced during high temperature priming and thus may serve to integrate stress responses with light regulated development. The future study in this direction will be useful to understand how plants acclimatize to the changing environment and thus help in generating stress tolerant crops.

Highlights

Changes in the climatic conditions because of global warming are imposing challenges on plants by affecting the distribution of biotic and abiotic factors [1]
Among them osa-miR169 was one of the largest families represented by 19 members that were regulated by cues from light and heat stress (HS). miR169 is a highly conserved family and its expression levels are influenced by different abiotic stress conditions [17] [23] [34]
It has been clearly demonstrated that miR169 negatively regulates the transcript level of NF-YA subunit [35] and may potentially regulate many aspects of plant life including primary root elongation, flowering, gametogenesis, seed development, abscisic acid signaling, and responses to HS, drought and light [36] [37]

Summary

Introduction

Changes in the climatic conditions because of global warming are imposing challenges on plants by affecting the distribution of biotic and abiotic factors [1] These stresses impact many important physiological processes, which lead to the loss in. High temperature stress (HS) causes protein denaturation, increased fluidity of membrane lipids and elevated lipid peroxidation [4] leading to lower photosynthetic rate, reduced seed germination and emergence [5] [6]. At reproductive stages, it causes anther indehiscence, spikelet sterility, fruit abscission and lower rice seed-sets [7]. It was demonstrated that light primes detoxification of the thermally induced reactive oxygen species during heat stress in Arabidopsis [11]

Methods

Results

Conclusion