Cytokinin Perception in Ancient Plants beyond Angiospermae

International Journal of Molecular Sciences

Alexander Heyl¹  Pavel P. Pashkovskiy²  Yulia A. Myakushina²  Ekaterina M. Savelieva²  Dmitry V. Arkhipov²  Sergey N. Lomin²  Georgy A. Romanov² 

[1] Biology Department, Adelphi University, Science 116, 1 South Avenue, Garden City, NY 11530-070, USA;Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya 35, 127276 Moscow, Russia;

关键词: cytokinin;    receptor;    signaling;    plant evolution;    binding affinity;    ligand preference;   

DOI  :  10.3390/ijms222313077

来源: DOAJ

【 摘 要 】

Cytokinins (CKs) control many plant developmental processes and responses to environmental cues. Although the CK signaling is well understood, we are only beginning to decipher its evolution. Here, we investigated the CK perception apparatus in early-divergent plant species such as bryophyte Physcomitrium patens, lycophyte Selaginella moellendorffii, and gymnosperm Picea abies. Of the eight CHASE-domain containing histidine kinases (CHKs) examined, two CHKs, PpCHK3 and PpCHK4, did not bind CKs. All other CHK receptors showed high-affinity CK binding (K_D of nM range), with a strong preference for isopentenyladenine over other CK nucleobases in the moss and for trans-zeatin over cis-zeatin in the gymnosperm. The pH dependences of CK binding for these six CHKs showed a wide range, which may indicate different subcellular localization of these receptors at either the plasma- or endoplasmic reticulum membrane. Thus, the properties of the whole CK perception apparatuses in early-divergent lineages were demonstrated. Data show that during land plant evolution there was a diversification of the ligand specificity of various CHKs, in particular, the rise in preference for trans-zeatin over cis-zeatin, which indicates a steadily increasing specialization of receptors to various CKs. Finally, this distinct preference of individual receptors to different CK versions culminated in vascular plants, especially angiosperms.

【 授权许可】

Unknown