Related Experiment Video
Updated: Aug 11, 2026
06:16
mirMachine: A One-Stop Shop for Plant miRNA Annotation
Published on: May 1, 2021
microRNA-mediated control of cell fate specification and patterning in Marchantia polymorpha
Adolfo Aguilar-Cruz1, Eduardo Flores-Sandoval2,3, Ye Xu4
1Instituto de Biotecnología y Ecología Aplicada (INBIOTECA), Universidad Veracruzana, Avenida de las Culturas Veracruzanas 101, Col. Emiliano Zapata, C.P. 91090, Xalapa, Veracruz, México.
The New Phytologist
|August 9, 2026
Summary
MicroRNAs (miRNAs) are crucial for plant development. The study reveals that MpDCL1a in Marchantia polymorpha is essential for miRNA biogenesis and that miR166/HD-ZIP regulates auxin for plant body development.
Area of Science:
- Plant molecular biology
- Developmental biology
- Evolutionary biology
Background:
- MicroRNAs (miRNAs) are key regulators of eukaryotic gene expression.
- DICER-LIKE 1 (DCL1) is the master gene for miRNA biogenesis in plants.
- Marchantia polymorpha serves as a model for understanding early land plant evolution.
Purpose of the Study:
- To investigate the function and evolution of miRNAs in land plants.
- To characterize the role of MpDCL1a in Marchantia polymorpha.
- To elucidate the miR166/CLASS III HD-ZIP regulatory circuit's function.
Main Methods:
- CRISPR-Cas9-mediated genomic editing to create MpDCL1a loss-of-function mutants.
- Functional characterization of mutants in Marchantia polymorpha.
- Comparative analysis to infer ancestral land plant characteristics.
Main Results:
- MpDCL1a is indispensable for miRNA biogenesis in Marchantia polymorpha.
- miR166/Homeodomain Zipper Class III pathway regulates auxin synthesis.
- This pathway is critical for cell identity, patterning, meristem function, and plant body development.
Conclusions:
- DCL1, Class III HD-ZIP, miR166, and auxin were integral to the development of the last common ancestor of land plants.
- This study provides a framework for understanding plant cell specification and patterning principles.
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