• The cytokinin signaling pathway consists of sensor kinases, histidine phosphotransfer proteins, and response regulators. (wikipedia.org)
  • In this system, cytokinin sensor kinases are activated by the presence of cytokinins. (wikipedia.org)
  • Cytokinins act in a restricted region of the root meristem, and their signaling and regulation of genes occurs through a multi-step phosphorelay mediate by cytokinin histidine sensor kinases, histidine phosphotransfer proteins, and cytokinin response regulator proteins. (wikipedia.org)
  • Cytokinin sensor kinases are the initial sensors that detect and are bound by cytokinins. (wikipedia.org)
  • Research with maize and Arabidopsis thaliana suggest that some cytokinin sensor kinases bind multiple types of cytokinins while other cytokinin sensor kinases are specific for distinct cytokinins. (wikipedia.org)
  • Histidine phosphotransfer proteins transfer the phosphate in the multistep phosphorelay signaling pathway from cytokinin sensor kinases to their final target, cytokinin response regulators. (wikipedia.org)
  • We used loss-of-function mutants to study three Arabidopsis thaliana sensor histidine kinases, AHK2, AHK3, and CRE1/AHK4, known to be cytokinin receptors. (nih.gov)
  • The response regulators can then serve as positive or negative regulators of the signaling mechanism and affect gene expression within the plant cells. (wikipedia.org)
  • Cytokinin response regulators proteins are the final target of the two-step phosphorelay. (wikipedia.org)
  • Type A cytokinin response regulators serve as negative regulators for cytokinin signaling. (wikipedia.org)
  • Cytokinin causes the rapid induction of type A response regulators. (wikipedia.org)
  • Expression of type A cytokinin response regulators decreases sensitivity to cytokinins, and a lack of type-A cytokinin response regulators leads to increased sensitivity to cytokinins. (wikipedia.org)
  • Type A cytokinin response regulators can act as negative regulators of cytokinin signaling by either competing with type-B positive regulators or by regulating the pathway through direct and indirect interactions with other pathway mechanisms. (wikipedia.org)
  • Type A cytokinin response regulators are also likely involved in other processes. (wikipedia.org)
  • Type B cytokinin response regulators are the positive regulators that oppose the negative regulation of type A cytokinin response regulators in the two-component cytokinin signaling pathway. (wikipedia.org)
  • Differing expression of type-B cytokinin response regulators likely play a role in controlling cellular response to cytokinins. (wikipedia.org)
  • The major family of type-B cytokinin response regulators are expressed in locations on the plant that are heavily influenced by cytokinins. (wikipedia.org)
  • Unchanged red light sensitivity of mutant hypocotyl elongation suggests that previously reported modulation of red light signaling by A-type response regulators may not depend on cytokinin. (nih.gov)
  • Together, the analyses reveal partially redundant functions of the cytokinin receptors and prominent roles for the AHK2/AHK3 receptor combination in quantitative control of organ growth in plants, with opposite regulatory functions in roots and shoots. (nih.gov)
  • AHP4, however, might play a negative role in cytokinin responses. (wikipedia.org)
  • The complex nature of growth regulation under stress has been highlighted in studies of plant responses to soil water deficit at developmental, physiological, and molecular levels. (stationzilla.com)
  • During drought, the body's own endogenous ABA is produced rapidly, setting off a chain reaction of physiological responses including the closure of stomata, controlled by a signal transduction network. (stationzilla.com)
  • Responses to abiotic and biotic stresses - from the cellular level to fruit development - contributions of the Czech Centre for Experimental Plant Biology. (muni.cz)
  • Plant responses to ambient temperature fluctuations and water-limiting conditions: a proteome-wide perspective. (muni.cz)
  • A cytokinin signaling and response regulator protein is a plant protein that is involved in a two step cytokinin signaling and response regulation pathway. (wikipedia.org)
  • The current model of cytokinin signaling and response regulation shows that it works as a multi-step phosphorelay two-component signaling system. (wikipedia.org)
  • This result supports a negative regulatory role for cytokinin in root growth regulation. (nih.gov)
  • Leaves of ahk2 ahk3 mutants formed fewer cells, had reduced chlorophyll content, and lacked the cytokinin-dependent inhibition of dark-induced chlorophyll loss, indicating a prominent role of AHK2 and, particularly, AHK3 in the control of leaf development. (nih.gov)
  • Actively growing plants respire heavily, using up food quickly. (stationzilla.com)
  • Plants use molecular mechanisms to reduce resource use and regulate growth in harsh conditions. (stationzilla.com)
  • Respiration is how plants convert food into energy for system processes. (stationzilla.com)
  • With low water levels reducing a plants' ability to photosynthesize, its system processes slow down, causing reduced or delayed growth, discolored leaves, and flower or fruit drop. (stationzilla.com)
  • These regulators play a critical role in early response to cytokinin. (wikipedia.org)
  • A significant abiotic stressor that affects plant growth and development is drought. (stationzilla.com)
  • Photosynthesis serves as the foundation for plant growth. (stationzilla.com)
  • In regions with low water availability, drought can be chronic or random and unpredictable due to weather changes during plant growth. (stationzilla.com)
  • Increased cytokinin content of receptor mutants indicates a homeostatic control of steady state cytokinin levels through signaling. (nih.gov)
  • Genetic analysis indicated a cytokinin-dependent endospermal and/or maternal control of embryo size. (nih.gov)
  • This type of system is similar to two-component signaling systems in bacteria. (wikipedia.org)
  • As water moves through the system, minerals and nutrients are delivered to plants. (stationzilla.com)
  • Three cytokinin receptors (AHK2, AHK3, AHK4) contain a structure of cyclase/HK-associated sensory extracellular (CHASE) domain which is the putative site for the recognition of cytokinin [ 6 ]. (biomedcentral.com)
  • cytokinin receptors, ethylene receptors and phytochromes. (biomedcentral.com)
  • The core abscisic acid (ABA) signaling pathway consists of receptors, phosphatases, kinases and transcription factors, among them ABA INSENSITIVE 5 (ABI5) and ABRE BINDING FACTORs/ABRE-BINDING PROTEINs (ABFs/AREBs), which belong to the BASIC LEUCINE ZIPPER (bZIP) family and control expression of stress-responsive genes. (mdpi.com)
  • The current model of cytokinin signaling and response regulation shows that it works as a multi-step phosphorelay two-component signaling system. (wikipedia.org)
  • Cytokinins act in a restricted region of the root meristem, and their signaling and regulation of genes occurs through a multi-step phosphorelay mediate by cytokinin histidine sensor kinases, histidine phosphotransfer proteins, and cytokinin response regulator proteins. (wikipedia.org)
  • Histidine phosphotransfer proteins transfer the phosphate in the multistep phosphorelay signaling pathway from cytokinin sensor kinases to their final target, cytokinin response regulators. (wikipedia.org)
  • Cytokinin response regulators proteins are the final target of the two-step phosphorelay. (wikipedia.org)
  • This group is unable to function as phosphotransmitter protein and participates in cytokinin signalling by inhibiting phosphorelay from phosphorylated AHP1 to ARR1. (biomedcentral.com)
  • Recently, we reported that Pi starvation signaling is affected by abiotic stresses such as salt, abscisic acid, and drought. (molcells.org)
  • The cytokinin signaling pathway consists of sensor kinases, histidine phosphotransfer proteins, and response regulators. (wikipedia.org)
  • In addition to the free base forms, cytokinins can also be present in the plant as a riboside (in which a ribose sugar is attached to the 9 nitrogen of the purine ring) or a ribotide (in which the ribose moiety contains a phosphate group). (bioone.org)
  • The maintenance of inorganic phosphate (Pi) homeostasis is essential for plant growth and yield. (molcells.org)
  • Later, zeatin was identified as the first naturally occurring cytokinin in immature maize endosperm ( Letham, 1973 ), and turns out to be the abundant cytokinin in coconut milk. (bioone.org)
  • Thus, we suggest the possibility of cross-talk between Pi starvation signaling and other environmental stress signaling pathways. (molcells.org)
  • Thus, Pi starvation signaling is strongly linked with numerous plant signaling pathways to maintain appropriate Pi homeostasis in response to changing environmental conditions. (molcells.org)
  • The signaling networks involved with plant responses to Pi starvation are well known, but the cross-talk between Pi starvation and other abiotic stress signaling pathways remains unclear. (molcells.org)
  • Plants tightly regulate the availability of GA by coordinating the activation and deactivation of multiple biosynthesis genes of GA in different tissues at various developmental stages [ 1 ]. (biomedcentral.com)
  • As a result, GA-deficient plants show many abnormal developmental characteristics such as smaller darker leaves and reduced internode length [ 5 ]. (biomedcentral.com)
  • This type of system is similar to two-component signaling systems in bacteria. (wikipedia.org)
  • These findings will help in understanding the functional mechanism of TCS proteins in plants in different conditions. (biomedcentral.com)
  • Type-A RRs are primary cytokinin response proteins consisting of a Rec domain along with a short C-terminal extensions. (biomedcentral.com)
  • The contrasting responses of some key flowering induction pathway genes provides new insights into the divergence of GA-DELLA regulations between annual and perennial species in GA-DELLA signaling. (biomedcentral.com)
  • In addition to basic characterization of DELLA protein genes in the GA signal transduction [ 6 ], many DELLA target genes which control development of various traits in model and annual species, have also been identified [ 7 ]. (biomedcentral.com)
  • A cytokinin signaling and response regulator protein is a plant protein that is involved in a two step cytokinin signaling and response regulation pathway. (wikipedia.org)
  • The mutant vine carries a copy each of the wildtype GIBBERELLIC ACID-INSENSITIVE1 ( VvGAI1 ) and mutant ( Vvgai1 ) and manifests reduced internode length and short plant stature, which is a hallmark trait of DELLA mutants in many species. (biomedcentral.com)
  • The type-B cytokinin response regulator family consists of two subfamilies and one major subfamily. (wikipedia.org)
  • Type B cytokinin response regulators are the positive regulators that oppose the negative regulation of type A cytokinin response regulators in the two-component cytokinin signaling pathway. (wikipedia.org)
  • A critical gain-of-function mutation in the DELLA domain prevents the formation of a stable trimeric complex with GA:GID1 required for its eventual degradation, and thus instead maintains the negative regulation of GA signaling [ 4 ]. (biomedcentral.com)
  • Gibberellins (GAs) and their regulator DELLA are involved in many aspects of plant growth and development and most of our current knowledge in the DELLA-facilitated GA signaling was obtained from the studies of annual species. (biomedcentral.com)
  • Differing expression of type-B cytokinin response regulators likely play a role in controlling cellular response to cytokinins. (wikipedia.org)
  • This system plays an important role in signal transduction during various cellular processes, including fruit ripening and response to multiple environmental cues. (biomedcentral.com)
  • The two-component system (TCS) is one of the most evolutionarily conserved signalling cascade present from prokaryotes to eukaryotes. (biomedcentral.com)
  • In higher plants, zeatin occurs in both the cis and the trans configuration, and these forms can be interconverted by an enzyme known as zeatin isomerase. (bioone.org)
  • Many transcription factors, miRNAs, and transporters participate in the Pi starvation signaling pathway where their activities are modulated by sugar and phytohormone signaling. (molcells.org)
  • Type A cytokinin response regulators serve as negative regulators for cytokinin signaling. (wikipedia.org)
  • Cytokinin causes the rapid induction of type A response regulators. (wikipedia.org)
  • Expression of type A cytokinin response regulators decreases sensitivity to cytokinins, and a lack of type-A cytokinin response regulators leads to increased sensitivity to cytokinins. (wikipedia.org)
  • Type A cytokinin response regulators can act as negative regulators of cytokinin signaling by either competing with type-B positive regulators or by regulating the pathway through direct and indirect interactions with other pathway mechanisms. (wikipedia.org)
  • These regulators play a critical role in early response to cytokinin. (wikipedia.org)
  • The major family of type-B cytokinin response regulators are expressed in locations on the plant that are heavily influenced by cytokinins. (wikipedia.org)
  • Environmental stresses significantly affect the uptake and utilization of nutrients by plants, but their effects on the Pi starvation response remain unclear. (molcells.org)
  • In the 1940s and 1950s, a wide variety of substances ranging from yeast extract to tomato juice were identified that that could initiate and sustain the proliferation of normal plant stem tissues in culture. (bioone.org)
  • To understand GA-DELLA signaling in perennial species, we created ten GA-insensitive transgenic grapevines carrying a DELLA mutant allele ( Vvgai1 ) in the background of Vitis vinifera 'Thompson Seedless' and conducted comprehensive analysis of their RNA expression profiles in the shoot, leaf and root tissues. (biomedcentral.com)
  • Cytokinins participate in short and long-distance signaling and are transported for this signaling through the xylem of plants. (wikipedia.org)
  • Though members of TCS have been identified in a few plants, no detailed analysis has been carried out in banana. (biomedcentral.com)
  • Plants have evolved strategies to cope with Pi starvation at the transcriptional, post-transcriptional, and post-translational levels, which maximizes its availability. (molcells.org)
  • 3 Institute of Plant Sciences, Department of Plant Physiology, University of Graz, 8010 Graz, Austria (T.W. (nih.gov)
  • 6 Institute of Plant Sciences, Department of Plant Physiology, University of Graz, 8010 Graz, Austria (T.W.) [email protected] [email protected]. (nih.gov)