@article{20818, abstract = {This study demonstrates that Marchantia non-canonical PINs are predominantly localized to the plasma membrane, with MpPINX and MpPINW exhibiting asymmetric distribution. A newly identified miniW domain within the MpPINW hydrophilic loop governs subcellular trafficking and asymmetric PM localization of non-canonical PINs in Marchantia.}, author = {Tang, Han and Smoljan, Adrijana and Zou, Minxia and Zhang, Yuzhou and Lu, Kuan Ju and Friml, Jiří}, issn = {1365-3040}, journal = {Plant Cell and Environment}, number = {3}, pages = {1505--1508}, publisher = {Wiley}, title = {{The miniW domain directs polarized membrane localization of non-canonical PINs in Marchantia polymorpha}}, doi = {10.1111/pce.70295}, volume = {49}, year = {2026}, } @article{19420, abstract = {Auxin and its PIN-FORMED (PIN) exporters are essential for tissue repair and regeneration in flowering plants. To gain insight into the evolution of this mechanism, we investigated their roles in leaves excised from Physcomitrium patens, a bryophyte known for its remarkable cell reprogramming capacity. We used various approaches to manipulate auxin levels, including exogenous application, pharmacological manipulations, and auxin biosynthesis mutants. We observed no significant effect on the rate of cell reprogramming. Rather, our analysis of auxin dynamics revealed a decrease in auxin levels upon excision, which was followed by a local increase before the reprogramming process began. Mutant analysis revealed that PpPINs are required for effective cell reprogramming, and endogenously expressed PpPINA-GFP accumulates polarly at sites that will develop into future filamentous stem cells. In addition, hyperpolarized PpPINA variants carrying mutated phosphorylation sites showed a marked delay in reprogramming, whereas endogenous or nonpolar versions do not have this effect. These results underscore that both the levels and the polarity of PpPINA are important for efficient cell reprogramming. Overall, these findings highlight the pivotal role of PIN polarity in plant regeneration. Furthermore, they suggest that understanding polarity mechanisms could have broader implications for improving regenerative processes across various plant species.}, author = {Tang, Han and Chen, L and Friml, Jiří}, issn = {1471-9053}, journal = {Plant and Cell Physiology}, publisher = {Oxford University Press}, title = {{Auxin fluctuation and PIN polarization in moss leaf cell reprogramming.}}, doi = {10.1093/pcp/pcaf008}, year = {2025}, } @article{14251, abstract = {The phytohormone auxin and its directional transport through tissues play a fundamental role in development of higher plants. This polar auxin transport predominantly relies on PIN-FORMED (PIN) auxin exporters. Hence, PIN polarization is crucial for development, but its evolution during the rise of morphological complexity in land plants remains unclear. Here, we performed a cross-species investigation by observing the trafficking and localization of endogenous and exogenous PINs in two bryophytes, Physcomitrium patens and Marchantia polymorpha, and in the flowering plant Arabidopsis thaliana. We confirmed that the GFP fusion did not compromise the auxin export function of all examined PINs by using radioactive auxin export assay and by observing the phenotypic changes in transgenic bryophytes. Endogenous PINs polarize to filamentous apices, while exogenous Arabidopsis PINs distribute symmetrically on the membrane in both bryophytes. In Arabidopsis root epidermis, bryophytic PINs show no defined polarity. Pharmacological interference revealed a strong cytoskeleton dependence of bryophytic but not Arabidopsis PIN polarization. The divergence of PIN polarization and trafficking is also observed within the bryophyte clade and between tissues of individual species. These results collectively reveal a divergence of PIN trafficking and polarity mechanisms throughout land plant evolution and a co-evolution of PIN sequence-based and cell-based polarity mechanisms.}, author = {Tang, Han and Lu, KJ and Zhang, Y and Cheng, YL and Tu, SL and Friml, Jiří}, issn = {2590-3462}, journal = {Plant Communications}, number = {1}, publisher = {Elsevier}, title = {{Divergence of trafficking and polarization mechanisms for PIN auxin transporters during land plant evolution}}, doi = {10.1016/j.xplc.2023.100669}, volume = {5}, year = {2024}, } @inbook{17085, abstract = {Mosses are a cosmopolitan group of land plants, sister to vascular plants, with a high potential for molecular and cell biological research. The species Physcomitrium patens has helped gaining better understanding of the biological processes of the plant cell, and it has become a central system to understand water-to-land plant transition through 2D-to-3D growth transition, regulation of asymmetric cell division, shoot apical cell establishment and maintenance, phyllotaxis and regeneration. P. patens was the first fully sequenced moss in 2008, with the latest annotated release in 2018. It has been shown that many gene functions and networks are conserved in mosses when compared to angiosperms. Importantly, this model organism has a simplified and accessible body structure that facilitates close tracking in time and space with the support of live cell imaging set-ups and multiple reporter lines. This has become possible thanks to its fully established molecular toolkit, with highly efficient PEG-assisted, CRISPR/Cas9 and RNAi transformation and silencing protocols, among others. Here we provide examples on how mosses exhibit advantages over vascular plants to study several processes and their future potential to answer some other outstanding questions in plant cell biology.}, author = {Floriach-Clark, Jordi and Tang, Han and Willemsen, Viola}, booktitle = {Model Organisms in Plant Genetics}, editor = {Abdurakhmonov, Ibrokhim Y.}, isbn = {9781839697500}, publisher = {IntechOpen}, title = {{Mosses: Accessible Systems for Plant Development Studies}}, doi = {10.5772/intechopen.100535}, year = {2022}, } @article{15266, abstract = {Plant pathogens often exploit a whole range of effectors to facilitate infection. The RXLR effector AVR1 produced by the oomycete plant pathogen Phytophthora infestans suppresses host defense by targeting Sec5. Sec5 is a subunit of the exocyst, a protein complex that is important for mediating polarized exocytosis during plant development and defense against pathogens. The mechanism by which AVR1 manipulates Sec5 functioning is unknown. In this study, we analyzed the effect of AVR1 on Sec5 localization and functioning in the moss Physcomitrium patens. P. patens has four Sec5 homologs. Two (PpSec5b and PpSec5d) were found to interact with AVR1 in yeast-two-hybrid assays while none of the four showed a positive interaction with AVR1ΔT, a truncated version of AVR1. In P. patens lines carrying β-estradiol inducible AVR1 or AVR1ΔT transgenes, expression of AVR1 or AVR1ΔT caused defects in the development of caulonemal protonema cells and abnormal morphology of chloronema cells. Similar phenotypes were observed in Sec5- or Sec6-silenced P. patens lines, suggesting that both AVR1 and AVR1ΔT affect exocyst functioning in P. patens. With respect to Sec5 localization we found no differences between β-estradiol-treated and untreated transgenic AVR1 lines. Sec5 localizes at the plasma membrane in growing caulonema cells, also during pathogen attack, and its subcellular localization is the same, with or without AVR1 in the vicinity.}, author = {Overdijk, Elysa J. R. and Putker, Vera and Smits, Joep and Tang, Han and Bouwmeester, Klaas and Govers, Francine and Ketelaar, Tijs}, issn = {1932-6203}, journal = {PLoS One}, keywords = {Multidisciplinary}, number = {4}, publisher = {Public Library of Science}, title = {{Phytophthora infestans RXLR effector AVR1 disturbs the growth of Physcomitrium patens without affecting Sec5 localization}}, doi = {10.1371/journal.pone.0249637}, volume = {16}, year = {2021}, }