Isoprenoid and aromatic cytokinins occur in poplar as free compounds and constituents of tRNA, poplar isopentenyltransferases are involved in the production of isoprenoid cytokinins, while biosynthesis of their aromatic counterparts remains unsolved. Cytokinins are phytohormones with a fundamental role in the regulation of plant growth and development. They occur naturally either as isoprenoid or aromatic derivatives, but the latter are quite rare and less studied. Here, the spatial expression of all nine isopentenyl transferase genes of Populus × canadensis cv. Robusta (PcIPTs) as analyzed by RT-qPCR revealed a tissue preference and strong differences in expression levels for the different adenylate and tRNA PcIPTs. Together with their phylogeny, this result suggests a functional diversification for the different PcIPT proteins. Additionally, the majority of PcIPT genes were cloned and expressed in Arabidopsis thaliana under an inducible promoter. The cytokinin levels measured in the Arabidopsis-overexpressing lines as well as their phenotype indicate that the studied adenylate and tRNA PcIPT proteins are functional in vivo and thus will contribute to the cytokinin pool in poplar. We screened the cytokinin content in leaves of 12 Populus species by ultra-high performance-tandem mass spectrometry (UHPLC-MS/MS) and discovered that the capacity to produce not only isoprenoid, but also aromatic cytokinins is widespread amongst the Populus accessions studied. Important for future studies is that the levels of aromatic cytokinins transiently increase after daybreak and are much higher in older plants.

Department of Biochemistry Faculty of Science Palacký University Olomouc Šlechtitelů 27 78371 Olomouc Czech Republic

Department of Genetic Resources for Vegetables Medicinal and Special Plants Centre of the Region Hana for Biotechnological and Agricultural Research Crop Research Institute Šlechtitelů 29 78371 Olomouc Czech Republic

Department of Molecular Biology Faculty of Science Centre of the Region Hana for Biotechnological and Agricultural Research Palacký University Olomouc Šlechtitelů 27 78371 Olomouc Czech Republic

Department of Phytochemistry Faculty of Science Centre of the Region Hana for Biotechnological and Agricultural Research Palacký University Olomouc Šlechtitelů 27 78371 Olomouc Czech Republic

Department of Protein Biochemistry and Proteomics Faculty of Science Centre of the Region Hana for Biotechnological and Agricultural Research Palacký University Olomouc Šlechtitelů 27 78371 Olomouc Czech Republic

Zobrazit více v PubMed

Mol Biol Evol. 2000 Apr;17(4):540-52 PubMed

Plant Cell. 2011 Jan;23(1):69-80 PubMed

Symp Soc Exp Biol. 1957;11:118-30 PubMed

Plant J. 2018 Feb;93(4):686-702 PubMed

Plant Physiol. 2013 Dec;163(4):1568-83 PubMed

J Biol Chem. 2004 Oct 1;279(40):41866-72 PubMed

Plant J. 1999 Mar;17(6):615-26 PubMed

Planta. 1973 Jun;114(2):119-29 PubMed

Plant Cell Physiol. 2001 Jul;42(7):677-85 PubMed

J Exp Bot. 2012 Sep;63(15):5569-79 PubMed

Plant Mol Biol. 2008 Jun;67(3):215-29 PubMed

BMC Genomics. 2013 Dec 16;14:885 PubMed

FEBS Lett. 2002 Sep 11;527(1-3):315-8 PubMed

Plant Physiol. 2008 Nov;148(3):1189-200 PubMed

J Biol Chem. 2009 Mar 13;284(11):6600-4 PubMed

Nature. 2007 Feb 8;445(7128):652-5 PubMed

Plant Cell Physiol. 2004 Sep;45(9):1299-305 PubMed

J Mol Biol. 2000 Sep 8;302(1):205-17 PubMed

Plant J. 2004 Jan;37(1):128-38 PubMed

J Exp Bot. 2011 May;62(8):2431-52 PubMed

Plant Physiol. 1993 Jul;102(3):867-872 PubMed

J Exp Bot. 2015 Aug;66(16):4913-31 PubMed

J Exp Bot. 2011 May;62(8):2827-40 PubMed

Phytochemistry. 2008 Aug;69(11):2214-24 PubMed

Front Plant Sci. 2017 Aug 23;8:1473 PubMed

Plant Physiol. 1992 May;99(1):74-80 PubMed

Plant Physiol. 2003 Oct;133(2):462-9 PubMed

New Phytol. 2015 Dec;208(4):1149-56 PubMed

Curr Opin Plant Biol. 2009 Oct;12(5):527-38 PubMed

Proc Natl Acad Sci U S A. 2001 Aug 28;98(18):10487-92 PubMed

Biochimie. 1994;76(12):1152-60 PubMed

Science. 1995 Dec 22;270(5244):1986-8 PubMed

Proc Natl Acad Sci U S A. 2006 Oct 31;103(44):16598-603 PubMed

Plant Physiol. 2008 Mar;146(3):1155-64 PubMed

Plant Cell Environ. 2017 May;40(5):622-634 PubMed

Proc Natl Acad Sci U S A. 2008 Oct 21;105(42):16142-7 PubMed

Integr Comp Biol. 2002 Jul;42(3):454-62 PubMed

Front Plant Sci. 2019 Jan 11;9:1936 PubMed

Plant Physiol. 2006 Sep;142(1):54-62 PubMed

Proc Natl Acad Sci U S A. 2008 Dec 16;105(50):20032-7 PubMed

BMC Plant Biol. 2015 Mar 12;15:85 PubMed

Nucleic Acids Res. 2018 Jul 2;46(W1):W296-W303 PubMed

Science. 2006 Sep 15;313(5793):1596-604 PubMed

PLoS One. 2015 Sep 16;10(9):e0138468 PubMed

Trends Plant Sci. 2018 Mar;23(3):179-181 PubMed

Annu Rev Phytopathol. 2011;49:69-86 PubMed

Plant Cell. 2016 Jul;28(7):1602-15 PubMed

J Phycol. 2017 Jun;53(3):703-714 PubMed

Plant Physiol. 2003 Jan;131(1):167-76 PubMed

Bioessays. 2015 Apr;37(4):356-63 PubMed

Parasitol Int. 2018 Feb;67(1):47-58 PubMed

Nucleic Acids Res. 2010 Mar;38(5):1738-48 PubMed

Biochem Biophys Res Commun. 1999 Feb 16;255(2):328-33 PubMed

Physiol Plant. 2003 Apr;117(4):453-458 PubMed

Plant Cell Physiol. 2001 Feb;42(2):107-13 PubMed

Syst Biol. 2010 May;59(3):307-21 PubMed

Curr Opin Plant Biol. 2018 Aug;44:82-87 PubMed

Mol Cell. 2015 Mar 19;57(6):984-994 PubMed

J Biol Chem. 2001 Jul 13;276(28):26405-10 PubMed

Plant Physiol. 2009 Sep;151(1):433-47 PubMed

The Hulks and the Deadpools of the Cytokinin Universe: A Dual Strategy for Cytokinin Production, Translocation, and Signal Transduction

Characterization of five CHASE-containing histidine kinase receptors from Populus × canadensis cv. Robusta sensing isoprenoid and aromatic cytokinins