Sessa, G.; Carabelli, M.; Possenti, M.; Morelli, G.; Ruberti, I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int. J. Mol. Sci.2018, 19, 4047.
Sessa, G.; Carabelli, M.; Possenti, M.; Morelli, G.; Ruberti, I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int. J. Mol. Sci. 2018, 19, 4047.
Sessa, G.; Carabelli, M.; Possenti, M.; Morelli, G.; Ruberti, I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int. J. Mol. Sci.2018, 19, 4047.
Sessa, G.; Carabelli, M.; Possenti, M.; Morelli, G.; Ruberti, I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int. J. Mol. Sci. 2018, 19, 4047.
Abstract
HD-Zip proteins are unique to plants, and contain a homeodomain closely linked to a leucine zipper motif, which are involved in dimerization and DNA binding. Based on homology in the HD-Zip domain, gene structure and the presence of additional motifs, HD-Zips are divided into four families, HD-Zip I–IV. Phylogenetic and bioinformatics analysis of HD-Zip genes using transcriptomic and genomic datasets from a wide range of plant species indicate that the HD-Zip protein class was already present in green algae. Later, HD-Zips experienced multiple duplication events that promoted neo- and sub-functionalizations. HD-Zip proteins are known to control key developmental and environmental responses, and a growing body of evidence indicates a strict link between members of the HD-Zip II and III families and the auxin machineries. Interactions of HD-Zip proteins with other hormones such as brassinolide and cytokinin have also been described. However, it is striking that among the genes regulated by REV, a HD-Zip III protein playing a key role in apical development, are genes that mediate ABA signaling. Furthermore, HAT1 and HAT3, two HD-Zip II proteins involved in key developmental processes, repress ABA biosynthesis and signaling, indicating an essential role of these factors in adjusting development to changing environment.
Biology and Life Sciences, Cell and Developmental Biology
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