--- res: bibo_abstract: - In plants, the multistep phosphorelay (MSP) pathway mediates a range of regulatory processes, including those activated by cytokinins. The crosstalk between cytokinin response and light is known for a long time. However, the molecular mechanism underlying the interactionbetween light and cytokinin signaling remains elusive. In the screen for upstream regulators we identified a LONG PALE HYPOCOTYL (LPH) gene whose activity is indispensable for spatiotemporally correct expression of CYTOKININ INDEPENDENT-1 (CKI1), encoding the constitutively active sensor histidine kinase that activates MSP signaling. lph is a new allele of HEME OXYGENASE 1 (HY1) which encodes the key protein in the biosynthesis of phytochromobilin, a cofactor of photoconvertiblephytochromes. Our analysis confirmed the light-dependent regulation oftheCKI1 expression pattern. We show that CKI1 expression is under the control of phytochrome A (phyA), functioning as a dual (both positive and negative) regulator of CKI1 expression, presumably via the phyA-regulated transcription factors PHYTOCHROME INTERACTING FACTOR 3 (PIF3) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1). Changes in CKI1 expression observed in lph/hy1-7 and phy mutants correlatewithmisregulation of MSP signaling, changedcytokinin sensitivity and developmental aberrations,previously shown to be associated with cytokinin and/or CKI1 action. Besides that, we demonstrate novel role of phyA-dependent CKI1 expression in the hypocotyl elongation and hook development during skotomorphogenesis. Based on these results, we propose that the light-dependent regulation of CKI1 provides a plausible mechanistic link underlying the well-known interaction between light- and cytokinin-controlled plant development.@eng bibo_authorlist: - foaf_Person: foaf_givenName: Tereza foaf_name: Dobisova, Tereza foaf_surname: Dobisova - foaf_Person: foaf_givenName: Vendula foaf_name: Hrdinova, Vendula foaf_surname: Hrdinova - foaf_Person: foaf_givenName: Candela foaf_name: Cuesta, Candela foaf_surname: Cuesta foaf_workInfoHomepage: http://www.librecat.org/personId=33A3C818-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0003-1923-2410 - foaf_Person: foaf_givenName: Sarka foaf_name: Michlickova, Sarka foaf_surname: Michlickova - foaf_Person: foaf_givenName: Ivana foaf_name: Urbankova, Ivana foaf_surname: Urbankova - foaf_Person: foaf_givenName: Romana foaf_name: Hejatkova, Romana foaf_surname: Hejatkova - foaf_Person: foaf_givenName: Petra foaf_name: Zadnikova, Petra foaf_surname: Zadnikova - foaf_Person: foaf_givenName: Markéta foaf_name: Pernisová, Markéta foaf_surname: Pernisová - foaf_Person: foaf_givenName: Eva foaf_name: Benková, Eva foaf_surname: Benková foaf_workInfoHomepage: http://www.librecat.org/personId=38F4F166-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0002-8510-9739 - foaf_Person: foaf_givenName: Jan foaf_name: Hejátko, Jan foaf_surname: Hejátko bibo_doi: 10.1104/pp.16.01964 bibo_issue: '1' bibo_volume: 174 dct_date: 2017^xs_gYear dct_identifier: - UT:000402057200028 dct_language: eng dct_publisher: American Society of Plant Biologists@ dct_title: Light regulated expression of sensor histidine kinase CKI1 controls cytokinin related development@ ...