WUSCHEL controls meristem function by direct regulation of cytokinin-inducible response regulators

  title={WUSCHEL controls meristem function by direct regulation of cytokinin-inducible response regulators},
  author={Andrea Leibfried and Jennifer P. C. To and Wolfgang Busch and Sandra Stehling and Andreas Kehle and Monika Demar and Joseph J. Kieber and Jan U. Lohmann},
Plants continuously maintain pools of totipotent stem cells in their apical meristems from which elaborate root and shoot systems are produced. In Arabidopsis thaliana, stem cell fate in the shoot apical meristem is controlled by a regulatory network that includes the CLAVATA (CLV) ligand–receptor system and the homeodomain protein WUSCHEL (WUS). Phytohormones such as auxin and cytokinin are also important for meristem regulation. Here we show a mechanistic link between the CLV/WUS network and… 
The FANTASTIC FOUR proteins influence shoot meristem size in Arabidopsis thaliana
A family of four plant-specific proteins, encoded by the FANTASTIC FOUR (FAF) genes, has the potential to regulate shoot meristem size in Arabidopsis thaliana by modulating the CLV3-WUS feedback loop.
Hormonal control of the shoot stem-cell niche
The activity of both hormones directly converges on the promoters of two A-type ARABIDOPSIS RESPONSE REGULATOR genes, ARR7 and ARR15, which are negative regulators of cytokinin signalling and have important meristematic functions.
Cytokinin signaling as a positional cue for patterning the apical–basal axis of the growing Arabidopsis shoot meristem
A computational model representing a growing SAM is developed to suggest the plausibility that apically derived cytokinin and CLV signaling, together, act as positional cues for patterning the WUS domain within the stem cell niche.
A Two-Step Model for de Novo Activation of WUSCHEL during Plant Shoot Regeneration
The results provide important insights into the molecular framework for cytokinin-directed shoot regeneration and reveal a two-step mechanism for de novo activation of WUS, the homeodomain transcription factor for Arabidopsis thaliana.
ERECTA-Family Receptor Kinases Regulate Stem Cell Homeostasis via Buffering its Cytokinin Responsiveness in the Shoot Apical Meristem
It is reported that members of the Arabidopsis ERECTA (ER) receptor kinase family redundantly play a significant role in the regulation of stem cell homeostasis and suggested that the ER family regulates stem cellHomeostasis via buffering its cytokinin responsiveness in the SAM.
Dynamic and Compensatory Responses of Arabidopsis Shoot and Floral Meristems to CLV3 Signaling[W]
It is shown that meristem homeostasis tolerates variation in CLV3 levels over a 10-fold range and that high-level CLV 3 signaling can be partially compensated with time, indicating that the level of CLV2 expression communicates only limited information on stem cell number to the underlying OC cells.
Flowering and determinacy in Arabidopsis.
  • R. Sablowski
  • Environmental Science
    Journal of experimental botany
  • 2007
In Arabidopsis, WUSCHEL (WUS) specifies the self-renewing cells at the core of the shoot meristems and is a key target in the control of meristem stability, and these genes participate in a series of regulatory feedback loops that maintain stable expression patterns or promote sharp developmental transitions.
Shoot stem cell specification in roots by the WUSCHEL transcription factor
The present research shows that activation of WUS function in the root inhibits the responses to exogenous auxin and suppresses the initiation and growth of lateral roots, and provides evidence for the manner by which WUS specifies stem-cell identity: by affecting auxin responses, by reducing the cell mitotic activity and by repressing other developmental pathways.


The WUSCHEL and SHOOTMERISTEMLESS genes fulfil complementary roles in Arabidopsis shoot meristem regulation.
The results suggest that WUS and STM share labour in the shoot apical meristem: WUS specifies a subset of cells in the centre as stem cells, while STM is required to suppress differentiation throughout the meristsem dome, thus allowing stem cell daughters to be amplified before they are incorporated into organs.
Regulation of CLV3 Expression by Two Homeobox Genes in Arabidopsis1
It is found that expression of CLV3 depends on WUS function only in the embryonic shoot meristem, and at later developmental stages, WUS promotes the level ofCLV3 expression, together with STM.
Control of phyllotaxy by the cytokinin-inducible response regulator homologue ABPHYL1
It is proposed that ABPH1 controls phyllotactic patterning by negatively regulating the cytokinin-induced expansion of the shoot meristem, thereby limiting the space available for primordium initiation at the apex.
Two-component circuitry in Arabidopsis cytokinin signal transduction
A eukaryotic two-component signalling circuit that initiates cytokinin signalling through distinct hybrid histidine protein kinase activities at the plasma membrane is identified.
Signaling of cell fate decisions by CLAVATA3 in Arabidopsis shoot meristems.
Genetic analysis indicates that CLV1, which encodes a receptor kinase, acts with CLV3 to control the balance between meristem cell proliferation and differentiation in Arabidopsis thaliana plants with loss-of-function mutations in the CLAVATA genes.
The WUSCHEL gene is required for shoot and floral meristem integrity in Arabidopsis.
The results suggest that the WUS gene is specifically required for central meristem identity of shoot and floral meristems to maintain their structural and functional integrity.
Dependence of stem cell fate in Arabidopsis on a feedback loop regulated by CLV3 activity.
Transgenic plants overexpressing CLV3 are used to show that meristem cell accumulation and fate depends directly on the level ofCLV3 activity and that CLV 3 signaling occurs exclusively through a CLV1/CLV2 receptor kinase complex.