Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/24/2017
Publication Date: 11/14/2017
Citation: Fletcher, J.C. 2017. State of the art: trxG factor regulation of post-embryonic plant development. Frontiers in Plant Science. 8:1925. doi:10.3389/fpls.2017.01925.
Interpretive Summary: One of the most fundamental activities in plant and animal cells is turning on or off various genes that are required to make the different tissue and organs of the body during development. Turning genes on or off requires many sets of proteins, including those that control how the DNA of the genes is packaged into the cell nucleus in a tiny ‘string of beads’ formation called chromatin. Proteins called PcG factors act to turn off genes by modifying chromatin whereas trxG factors act oppositely to turn on gene expression. Because of their importance, there is a great deal of interest in determining which PcG factors and trxG factors are involved in different aspects of plant growth. In this article I summarize recent insights into the role of trxG factors in controlling plant development, focusing in particular on recent reports of trxG activities in key processes such as root growth and flower formation. I also discuss our understanding of which trxG proteins come together to form large complexes, an activity that is well known to be essential for trxG activity in animals but is only beginning to be worked out in plant systems.
Technical Abstract: Multicellular organisms rely on the precise and consistent regulation of gene expression to direct their development in tissue- and cell-type specific patterns. This regulatory activity involves arrays of DNA-binding transcription factors and epigenetic factors that modify chromatin structure. Among the chromatin modifiers, trithorax (trxG) and Polycomb (PcG) group proteins play important roles in orchestrating the stable activation and repression of gene expression, respectively. These proteins have generally antagonistic functions in maintaining cell and tissue homeostasis as well as in mediating widespread transcriptional reprogramming during developmental transitions. Plants utilize multiple trxG factors to regulate gene transcription as they modulate their development in response to both endogenous and environmental cues. Here I will discuss the roles of trxG factors and their associated proteins in post-embryonic plant development.