ATG genes, new players on early Fe toxicity response in rice (Oryza sativa)

Abstract

Rice is a staple food for more than half of the world's population and is directly associated with food security. An additional 100 million tonnes of rice production is estimated to be needed to meet the demand of 9.1 billion people by 2050 (Jaggard, Qi, & Ober, 2010; Mahender, Swamy, Anandan, & Ali, 2019). However, the genetic gain for rice grain yield has stagnated over the past decade, resulting in productivity plateaus even in favourable environments. Also, rice growth and development faces different abiotic stresses such as drought, cold, heat, salinity, acidic soils, nutritional deficiencies, and soil toxicities, which cause significant losses in grain yield (Mahender et al., 2019). To deal with the environmental challenges, a better understanding of genetic responses to abiotic stress is needed, particularly those mechanisms that promote plant survival at the cellular and organism level. Autophagy (meaning self-eating) is one of these mechanisms, in which macromolecules and cellular components are recycled into vacuoles for reuse. This process is crucial for the maintenance of cellular homeostasis, acts on normal conditions, and is stimulated under adverse conditions (Avin-Wittenberg, 2019; Signorelli, Tarkowski, Van den Ende, & Bassham, 2019). In plants, autophagy has been described in Arabidopsis

Elucidation of Novel cis-Regulatory Elements and Promoter Structures Involved in Iron Excess Response Mechanisms in Rice Using a Bioinformatics Approach

“…Some WRKY TFs are involved in the Fe toxicity response in rice ( Ricachenevsky et al, 2010 ; Finatto et al, 2015 ; Viana et al, 2017 ). WRKY transcription factors are also involved in transcriptional regulation of OsATG (autophagy-related) genes under Fe toxicity, and W-box CREs targeted by WRKY TFs are enriched in the promoters of OsATG genes ( Maltzahn et al, 2020 ). They suggested these genes are involved in the early Fe toxicity response and may be regulated via WRKY.…”

“…They reported that CREs related to auxin-responsive element and ABA-responsive elements are present. Maltzahn et al (2020) reported that the promoters of rice autophagy-related genes (OsATG) are rich in W-box CREs that bind WRKY transcription factors, suggesting the possible involvement of these genes in the early response to Fe toxicity. However, the specific and core CREs in promoter sequences that coordinate the expression of most Fe excess-responsive genes in rice remain unknown.…”