Regulon: An overview of plant abiotic stress transcriptional regulatory system and role in transgenic plants

Abstract

Population growth is increasing rapidly around the world, in these consequences we need to produce more foods to full fill the demand of increased population. The world is facing global warming due to urbanizations and industrialization and in this concerns plants exposed continuously to abiotic stresses which is a major cause of crop hammering every year. Abiotic stresses consist of Drought, Salt, Heat, Cold, Oxidative and Metal toxicity which damage the crop yield continuously. Drought and salinity stress severally affected in similar manner to plant and the leading cause of reduction in crop yield. Plants respond to various stimuli under abiotic or biotic stress condition and express certain genes either structural or regulatory genes which maintain the plant integrity. The regulatory genes primarily the transcription factors that exert their activity by binding to certain cis DNA elements and consequently either up regulated or down regulate to target expression. These transcription factors are known as masters regulators because its single transcript regulate more than one gene, in this context the regulon word is fascinating more in compass of transcription factors. Progress has been made to better understand about effect of regulons (AREB/ABF, DREB, MYB, and NAC) under abiotic stresses and a number of regulons reported for stress responsive and used as a better transgenic tool of Arabidopsis and Rice.

A Pathogen-Inducible Rice NAC Transcription Factor ONAC096 Contributes to Immunity Against Magnaprothe oryzae and Xanthomonas oryzae pv. oryzae by Direct Binding to the Promoters of OsRap2.6, OsWRKY62, and OsPAL1

“…NAC TFs have been shown to be involved in plant developmental processes, including leaf senescence, fruit ripening, secondary cell wall synthesis, lateral root development and seed size (Kim et al, 2016;Forlani et al, 2021;Kou et al, 2021;Singh et al, 2021). On the other hand, NAC TFs have also been demonstrated to regulate plant response to abiotic and biotic stress, including drought, salt, heat, cold, oxidative, metal toxicity, and pathogen attack (Puranik et al, 2012;Shao et al, 2015;Baillo et al, 2019;Yuan et al, 2019a,b;Bian et al, 2020;Diao et al, 2020;Ritonga et al, 2021;Warsi et al, 2021).…”

Salt Stress and Plant Molecular Responses

“…Very few regulons have been reported in plants in response to abiotic stresses. One of them is DREB regulon and its overexpression exhibited tolerance against major abiotic stresses such as cold, drought, and salt stress [56]. The wheat cultivars exposed to long-term salinity and bZIP gene expression was noticed significantly upregulated that conferred salinity tolerance in sensitive cultivars, contrarily its expression was lower in tolerant cultivars [57].…”

Physiological and Biochemical Effects of Drought Stress in Stevia (Stevia rebaudiana Bertoni)

“…Sıcak, soğuk, tuzluluk, kuraklık ve ağır metal toksisitesi gibi çeşitli abiyotik stres faktörleri bitkilerin büyümesini ve gelişmesini sınırlandırarak sürdürülebilir tarım açısından tehdit oluşturmaktadır [14]. Özellikle kuraklık, bitkinin yeterli su alınımını engelleyerek büyümeyi, besin emilimini, gen ifadesini, ürün verimini ve kalitesini olumsuz etkilemektedir [15].…”