Dynamics ofmiRNAmediated regulation of legume symbiosis

Abstract

Symbiotic nitrogen fixation in legume nodules is important in soils with low nitrogen availability. The initiation and sustainability of symbiosis require cellular reprogramming that involves the miRNA-mediated inhibition or activation of specific nodulation genes. The high-throughput sequencing of small RNA libraries has identified miRNAs and their targets, which are the major players in the post-transcriptional gene regulation (PTGS) of the different stages of legume-rhizobia symbiosis ranging from bacterial colonization and organogenesis to symbiotic nitrogen fixation. Here, we present an overview of information obtained from the miRNA libraries from nodulating tissues that have been sequenced to date. The functional analysis of miRNAs has revealed roles in phytohormone homeostasis and spatio-temporal regulation, as well as the mobility of miRNAs and their functions in shoot to root signalling that affects diverse functions, including bacterial entry, meristem division and differentiation, nitrogen fixation and senescence. Furthermore, small RNA fragments of rhizobial origin repress complementary plant mRNAs. We also consider the roles of miRNAs in determinate or indeterminate nodules. Taken together, this overview confirms that miRNAs are master regulators of the legume-rhizobia symbiosis.

Genetic and molecular mechanisms underlying root architecture and function under heat stress—A hidden story

“…Crosstalk of phytohormones involves complex and intricate molecular machinery that regulates root architecture in plants (Sharma et al, 2021). Several plant growth regulators have been characterized to regulate the development of primary and lateral root primordia as well as root symbiosis (Mishra, Suri, et al, 2021; Tiwari & Bhatia, 2020; Tiwari, Pandey, Singh, & Bhatia, 2021; Tiwari, Pandey, Singh, Yadav, et al, 2021). Apart from regulatory roles in root architecture development and maintenance, they are also implicated in heat stress responses (N. Li et al, 2021).…”

Effective Use of Water in Crop Plants in Dryland Agriculture: Implications of Reactive Oxygen Species and Antioxidative System

“…The intricate interaction between ROS and these signaling cues orchestrate a cardinal response involving an appropriate molecular, metabolic, and physiological acclimation responses, allowing the plant to survive under adverse environmental conditions ( Zhu et al, 2016 ; Waszczak et al, 2018 ; Kollist et al, 2019 ; Zandalinas et al, 2020 ). The cell division and expansion are critical events of the plant growth process that are often affected by environmental stresses and are under the control of ROS, phytohormones, transcription factors, kinases, and small RNAs ( Huang et al, 2019 ; Mishra et al, 2021b ; Tiwari et al, 2021a , b , c ). The role of ROS in cell proliferation is also evident from reports that reveal manganese superoxide dismutase (MnSOD) regulating a redox cycle within the cell cycle ( Sarsour et al, 2014 ).…”

“… Huang et al (2020) reported that arbuscular mycorrhizal fungi (AMF) could utilize the MAPKs signaling pathway to enhance drought tolerance by using MAPK signaling as an intermediate pathway for interactions between AMF and their host apple plant. Besides, the extensive role of MAPKs, other kinases such as histidine kinases, CDPKs, leucine-rich repeat-receptor-like kinases, and serine-threonine protein kinases are also at the center of stress tolerance ( Mishra et al, 2021a ; Tiwari et al, 2021a , b ). Early leaf development is regulated by genes-encoding OsSIK2 , a protein kinase located in rice leaf and sheath plasma membrane.…”

Omics Path to Increasing Productivity in Less-Studied Crops Under Changing Climate—Lentil a Case Study

“…Transcriptomics is fundamental and comparatively economical among all omics strategies and, hence, most widely used till date ( Dumschott et al, 2020 ; Jung et al, 2020 ). The advent of NGS has further reduced the cost, accompanied with increased accuracy ( Kant et al, 2017 ; Tripathi et al, 2018 ; Tiwari and Bhatia, 2020 ; Tiwari et al, 2021a , c ). Various transcriptomic studies have been performed to get an insight into diverse functional aspects of lentil plants such as growth, development, response to stress, and marker identification, development, and application ( Kaur et al, 2011 ; Verma et al, 2013 ; Yilmaz Temel et al, 2015 ; Sudheesh et al, 2016b ; Barrios et al, 2017 ; Singh et al, 2017c , 2019b ; Khorramdelazad et al, 2018 ; Cao et al, 2019 ; García-García et al, 2019 ; Morgil et al, 2019 ; Wang et al, 2020 ).…”