Analysis of molecular and cellular mechanisms regulating CKX activity in plants
Final Report Abstract
The plant hormone cytokinin is a chemical signal that controls numerous developmental processes throughout the plant life cycle and it mediates responses to many environmental cues. The concentration of the plant hormone cytokinin is controlled through many metabolic reactions including oxidative degradation catalyzed by cytokinin oxidase/dehydrogenase (CKX) enzymes. The objective of this research project was to advance our understanding of this metabolic pathway, with special emphasis on the molecular and cellular mechanisms underlying the activity of CKX proteins. In this respect, the project has, for example, brought new relevant information about the subcellular localization of the proteins, highlighting the endoplasmic reticulum as a cellular compartment with a specific role in controlling cytokinin homeostasis. The relevance of different types of protein-protein interactions for regulating the CKX protein abundance and its physiological activity was revealed. Last but not least, the project discovered a novel regulatory mechanism of CKX gene expression, which involves the activity of long cis-encoded natural antisense transcripts. Hence, the research has contributed to the understanding of the role of long noncoding RNAs in gene regulation in plants.
Publications
- (2018) The cytokinin oxidase/dehydrogenase CKX1 is a membrane-bound protein requiring homooligomerization in the endoplasmic reticulum for its cellular activity. Plant Physiol. 176: 2024-2039
Niemann M.C.E., Weber H., Hluska T., Leonte G., Anderson S.M., Senes A., Werner T.
(See online at https://doi.org/10.1104/pp.17.00925)
