Tag: Jonathan H Dang

MUTE, Cell-State Switch and the Single Symmetric Division to Create Stomata

Transcriptomic Profiling of MUTE Target Genes Reveals a Framework of Stomatal Cell-State Switch

(A–E) Epidermal phenotypes of 3-day-old seedlings. Mock (A and C), iMUTE (B and D), and iSPCH (E). Mature stomata of mock (C) and iMUTE (D) cotyledon epidermis expressing GC GFP marker E994. Scale bars, 50 μm.

MUTE Directly Orchestrates Cell-State Switch and the Single Symmetric Division to Create Stomata

by Han S. K., Qi X., Sugihara K., Dang J. D., Endo T. A., Miller K. L., Kim E.-D., Miura T., Torii K. U. (2018)

Soon-Ki Han6 Xingyun Qi6 Kei Sugihara Jonathan H. Dang Takaho A. Endo Kristen L. Miller Eun-Deok Kim Takashi Miura Keiko U. Torii7

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in Dev. Cell 45(3): 303-315 –

https://www.cell.com/developmental-cell/fulltext/S1534-5807(18)30285-5 

Highlights

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    Comprehensive inventories of gene expression in stomatal differentiation reported

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    MUTE switches stomatal patterning program initiated by its sister bHLH, SPEECHLESS

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    MUTE directly induces cell-cycle genes and their direct transcriptional repressors

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    Incoherent feed-forward loop by MUTE ensures stomata composed of paired guard cells

Summary

Precise cell division control is critical for developmental patterning. For the differentiation of a functional stoma, a cellular valve for efficient gas exchange, the single symmetric division of an immediate precursor is absolutely essential. Yet, the mechanism governing this event remains unclear. Here we report comprehensive inventories of gene expression by the Arabidopsis bHLH protein MUTE, a potent inducer of stomatal differentiation.

MUTE switches the gene expression program initiated by SPEECHLESS. MUTE directly induces a suite of cell-cycle genes, including CYCD5;1, in which introduced expression triggers the symmetric divisions of arrested precursor cells in mute, and their transcriptional repressors, FAMA and FOUR LIPS.

The regulatory network initiated by MUTE represents an incoherent type 1 feed-forward loop. Our mathematical modeling and experimental perturbations support a notion that MUTE orchestrates a transcriptional cascade leading to a tightly restricted pulse of cell-cycle gene expression, thereby ensuring the single cell division to create functional stomata.

Autocrine regulation of stomatal differentiation

 

 

 

Autocrine regulation of stomatal differentiation potential by EPF1 and ERECTA-LIKE1 ligand-receptor signaling

Qi X., Han S.-K., Dang J. H., Garrick J. M., Ito M., Hofstetter A. K., Torii K. U. (2017)

  1. Xingyun Qi,
  2. Soon-Ki Han,
  3. Jonathan H Dang,
  4. Jacqueline M Garrick,
  5. Masaki Ito,
  6. Alex K Hofstetter,
  7. Keiko U Torii, 

 

in  eLife 2017;6:e24102 DOI: 10.7554/eLife.24102

https://elifesciences.org/articles/24102

Abstract

 

Development of stomata, valves on the plant epidermis for optimal gas exchange and water control, is fine-tuned by multiple signaling peptides with unique, overlapping, or antagonistic activities.

EPIDERMAL PATTERNING FACTOR1 (EPF1) is a founding member of the secreted peptide ligands enforcing stomatal patterning. Yet, its exact role remains unclear.

Here, we report that EPF1 and its primary receptor ERECTA-LIKE1 (ERL1) target MUTE, a transcription factor specifying the proliferation-to-differentiation switch within the stomatal cell lineages.

In turn, MUTE directly induces ERL1.

The absolute co-expression of ERL1 and MUTE, with the co-presence of EPF1, triggers autocrine inhibition of stomatal fate.

During normal stomatal development, this autocrine inhibition prevents extra symmetric divisions of stomatal precursors likely owing to excessive MUTE activity.

Our study reveals the unexpected role of self-inhibition as a mechanism for ensuring proper stomatal development and suggests an intricate signal buffering mechanism underlying plant tissue patterning.