Genetius

The study characterizes the single-copy S-nitrosoglutathione reductase 1 (MpGSNOR1) in the liverwort Marchantia polymorpha, showing that loss-of-function mutants generated via CRISPR/Cas9 exhibit marked morphological defects and compromised SNO homeostasis and immune responses. These findings indicate that GSNOR-mediated regulation of S‑nitrosylation is an ancient mechanism linking development and immunity in early land plants.

The study examines the structural basis and functional importance of proteasomal degradation of Auxin Response Factors (ARFs) in the liverwort Marchantia polymorpha, pinpointing a key residue required for degradation of both repressive B‑class MpARF2 and activating A‑class MpARF1. While MpARF2 degradation is essential across all life‑cycle stages for proper development, disrupting MpARF1 degradation has minimal impact on auxin response, indicating divergent evolutionary integration of the degradation mechanism.

The study investigates how the receptor kinase FERONIA senses mechanical cues to regulate growth in Marchantia vegetative propagules, using microfluidic growth assays, osmotic perturbations, cell‑wall analysis, and a mathematical model of wall expansion. Results show FERONIA independently controls tissue mechanical properties and growth rates via a positive feedback from elastic deformation and a negative feedback from wall expansion.

The study identifies the decapping proteins EDC4 and DCP1 as a cooperative selective autophagy receptor pair that mediates turnover of processing bodies in the early land plant Marchantia polymorpha. MpEDC4 binds ATG8 via a canonical AIM motif, while MpDCP1 uses a reverse AIM, and disruption of these motifs blocks P‑body degradation, a mechanism absent in Arabidopsis and humans. Heterologous expression of MpEDC4 in human cells also promotes degradation of α‑synuclein, highlighting a potential cross‑kingdom application.

The study investigates the function of two GT47B arabinan arabinosyltransferase genes (MpARADL1 and MpARADL2) in the liverwort Marchantia polymorpha, using loss‑of‑function and overexpression mutants combined with cell wall profiling techniques. While MpARADL2 mutants show reduced 1,5‑L‑arabinan epitopes in elaters, overall 5‑linked arabinose levels remain unchanged, indicating additional enzymes contribute to arabinan biosynthesis, and attempts to purify the proteins in HEK293 cells were unsuccessful, suggesting a conserved solubility requirement.

The study investigates meristem activity in the liverwort Marchantia polymorpha, revealing that simulated shade induces alternating inactivity of meristems. Transcriptomic analysis identified the cytochrome P450 enzyme MpCYP78E1 as a negative regulator of both meristem initiation and activity, with loss-of-function mutants showing increased active meristems and ectopic meristem formation. These findings highlight MpCYP78E1’s role in shaping shoot branching architecture.

The study characterizes MpCAFA, a combined CAPS‑FAP115 protein, in the liverwort Marchantia polymorpha and shows it is specifically expressed in antheridia where it localizes along spermatozoid cilia. Loss‑of‑function mutants display reduced swimming speed without affecting ciliary structure, chemotaxis, or fertility, indicating MpCAFA is essential for motility but not for other reproductive functions. Both the CAPS‑like and FAP115‑like domains are required for MpCAFA’s activity and ciliary localization.

This study characterizes cell wall glycans in eight tissues of the liverwort Marchantia polymorpha, revealing a generally typical land‑plant composition but with distinctive features such as abundant (1,5)-arabinan in sporophytes and unusually low overall pectin. Comparative analysis shows a diversified glycosyltransferase repertoire relative to Arabidopsis, and the authors provide a Gateway‑compatible library of 93 M. polymorpha GTs for future functional work.

The authors demonstrate that the MYB‑bHLH‑WDR (MBW) transcriptional complexes, known from seed plants, also form in the liverwort Marchantia polymorpha, indicating these complexes are ancestral to land plants. Functional assays reveal two MYB orthologs (MpMYB14, MpMYB02) depend on a single bHLH partner (MpbHLH12), while the WDR component could not be characterized due to lethal mutant phenotypes, and suggest ancestral regulation of flavonoid biosynthesis and a derived role in liverwort oil‑body maturation.

The authors adapt the OpenPlant CRISPR/Cas9 toolkit to express multiple gRNAs from a single transcript in Marchantia polymorpha by inserting tRNA sequences, markedly enhancing editing efficiency and scalability. Combined with an optimized thallus transformation protocol, this system provides a fast, versatile platform for functional genomics and extensive genome engineering in the liverwort model.