Plant hormones - Some glimpses on biosynthesis, signaling networks and cross talk

Authors: Mattoo, Autar; UPADHYAY, RAKESH - Purdue University

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 3/1/2019
Publication Date: 11/10/2019
Citation: Mattoo, A.K., Upadhyay, R.K. 2019. Plant hormones - Some glimpses on biosynthesis, signaling networks and cross talk. Book Chapter. In: Sensory Biology of Plants, Springer pp. 227-246.

Interpretive Summary: Plant hormones are structurally diverse and their biosynthetic precursors have been mostly identified and characterized. While it is understood that each hormone has a specific, independent mode of action, recent developments/advances in plant biology have also brought a new reality to fore on the complexity in hormonal involvement in plant biological processes. Plant hormones impact diverse plant processes, including growth and development, and crop responses to extreme environments. Specifically, several hormones singly and/or in combination with other hormone(s) interact to positively or negatively regulate a certain mode of action. This invited book chapter reviews latest developments in understanding how crop plants utilize hormonal crosstalk for sustenance of life and productivity during environmental extremes. Its contents will be of interest to biologists, academicians and scientists.

Technical Abstract: Plant hormones are major cellular signaling molecules that modulate growth, development and respond to internal and external cues in plants although differently than is understood about hormones specific to animals. The fortuitous discovery of hormones in animal/human systems and plants occurred around the similar time span. Hormone(s) are also functional in the same cells where they are synthesized as well as in the neighboring or distant cell. Although at least nine plant hormones are now recognized, many more could be discovered and characterized in the future. Their perception, intra- and inter-cellular movement/communication, and interaction with receptors and gene regulators is better understood now, however, the intimate details are yet to be discovered. Each plant hormone has a unique/specific function and also regulates networks of other hormones via cross talks involving specific transcription factors and small RNAs. This new knowledge has brought to light the fact that the regulation of plant physiological processes involves a complex cross-talk among different hormones. The new developments in various technologies, including forward genetics, ease of plant transformation systems, and the gain-of-function and loss-of-function model systems have contributed to the progress made thus far. This chapter provides salient features on hormone biology and selected cross talks between hormones in impacting various plant processes and the responses to abiotic stresses.