@article{22366,
  abstract     = {Gravitropism is a fundamental adaptive response in plants that enables directional growth to optimize resource acquisition. In this study, we employed forward genetic screening to identify Arabidopsis mutants with defective hypocotyl gravitropism and isolated the short and agravitropic hypocotyl in dark1 (sad1) mutant, which carries a point mutation (G110E) in the SAC1 gene encoding a phosphoinositide phosphatase. Deficiency of SAC1 disrupted gravity-induced polar localization of PIN3 in endodermal cells, impairing auxin redistribution and leading to hypocotyl gravitropism defects. Subcellular localization analysis revealed that SAC1 is partially localized to the PVC/tonoplast and participates in late endosomal trafficking. The sac1 mutation leads to abnormal vacuolar morphology, which is associated with defects in amyloplast sedimentation during the gravitropic response in Arabidopsis shoots. We further revealed that SAC1 interacts with GRV2, a key regulator of the late endocytic pathway, and that both proteins cooperatively regulate shoot gravitropism. In summary, this study identified SAC1 as a regulator of shoot gravitropism, revealing its important role in modulating vacuolar homeostasis, amyloplast sedimentation, PIN3 trafficking, and auxin distribution. These findings provide insights into the molecular mechanisms linking membrane transport to environmental adaptation in plants.},
  author       = {Sun, Lianghanxiao and Jia, Wenxin and Mao, Yanbo and Li, Xin and Kong, Mengjuan and She, Ji and Friml, Jiří and Tan, Shutang},
  issn         = {1365-313X},
  journal      = {The Plant Journal},
  keywords     = {auxin, SAC1, GRV2, PIN3, vacuole, gravitropism, Arabidopsis},
  number       = {1},
  publisher    = {Wiley},
  title        = {{Regulation of shoot gravitropism and branching angle by the GRV2-SAC1 axis in Arabidopsis}},
  doi          = {10.1111/tpj.71042},
  volume       = {127},
  year         = {2026},
}

@article{20187,
  abstract     = {Very long-chain fatty acids (VLCFAs), being constituents of different types of lipids, are critical factors in plant development, presumably due to their impact on the endomembrane system. The VLCFAs are synthesized in the endoplasmic reticulum by a heterotetrameric enzymatic complex including β-ketoacyl CoA reductase 1 (KCR1), whose mutant is lethal. Here, we describe the ectopic shoot meristems (esm) mutant, a viable kcr1 allele presumably affecting surface properties of the KCR1 protein. This kcr1-2 mutant shows reduced fatty acyl elongation that impacts VLCFAs. The kcr1-2 plants show severe defects during different stages of development, which all correlate with defects in polar localization and subcellular trafficking of PIN auxin transporters and resulting asymmetric auxin distribution. Detailed analysis of KCR1 expression and patterning defects in kcr1-2 suggests that KCR1 plays a role in delineating boundaries around meristematic and specialized differentiating tissues, including root and shoot meristems, initiating lateral roots, lateral root primordia, and trichomes. In these contexts, KCR1-produced VLCFAs may act in a non-cell-autonomous manner. Viable kcr1-2 represents a useful tool to study VLCFA roles in plant development and highlights VLCFAs as critical developmental factors at the interface of cell polarity and tissue development.},
  author       = {Babic, David and Abualia, Rashed and Fiedler, Lukas and Qi, Linlin and Tellier, Frédérique and Smoljan, Adrijana and Rakusova, Hana and Valošek, Petr and Han, Huibin and Benková, Eva and Faure, Jean Denis and Friml, Jiří},
  issn         = {1365-313X},
  journal      = {Plant Journal},
  number       = {3},
  publisher    = {Wiley},
  title        = {{Biosynthesis of very long-chain fatty acids is required for Arabidopsis auxin-mediated embryonic and post-embryonic development}},
  doi          = {10.1111/tpj.70396},
  volume       = {123},
  year         = {2025},
}

@article{12878,
  abstract     = {Salicylic acid (SA) plays important roles in different aspects of plant development, including root growth, where auxin is also a major player by means of its asymmetric distribution. However, the mechanism underlying the effect of SA on the development of rice roots remains poorly understood. Here, we show that SA inhibits rice root growth by interfering with auxin transport associated with the OsPIN3t- and clathrin-mediated gene regulatory network (GRN). SA inhibits root growth as well as Brefeldin A-sensitive trafficking through a non-canonical SA signaling mechanism. Transcriptome analysis of rice seedlings treated with SA revealed that the OsPIN3t auxin transporter is at the center of a GRN involving the coat protein clathrin. The root growth and endocytic trafficking in both the pin3t and clathrin heavy chain mutants were SA insensitivity. SA inhibitory effect on the endocytosis of OsPIN3t was dependent on clathrin; however, the root growth and endocytic trafficking mediated by tyrphostin A23 (TyrA23) were independent of the pin3t mutant under SA treatment. These data reveal that SA affects rice root growth through the convergence of transcriptional and non-SA signaling mechanisms involving OsPIN3t-mediated auxin transport and clathrin-mediated trafficking as key components.},
  author       = {Jiang, Lihui and Yao, Baolin and Zhang, Xiaoyan and Wu, Lixia and Fu, Qijing and Zhao, Yiting and Cao, Yuxin and Zhu, Ruomeng and Lu, Xinqi and Huang, Wuying and Zhao, Jianping and Li, Kuixiu and Zhao, Shuanglu and Han, Li and Zhou, Xuan and Luo, Chongyu and Zhu, Haiyan and Yang, Jing and Huang, Huichuan and Zhu, Zhengge and He, Xiahong and Friml, Jiří and Zhang, Zhongkai and Liu, Changning and Du, Yunlong},
  issn         = {1365-313X},
  journal      = {Plant Journal},
  number       = {1},
  pages        = {155--174},
  publisher    = {Wiley},
  title        = {{Salicylic acid inhibits rice endocytic protein trafficking mediated by OsPIN3t and clathrin to affect root growth}},
  doi          = {10.1111/tpj.16218},
  volume       = {115},
  year         = {2023},
}

@article{2993,
  abstract     = {Plant biology is currently experiencing a growing demand for easy and reliable mRNA and protein localisation techniques. Here, we present novel whole mount in situ hybridisation and immunolocalisation protocols, suitable to localise mRNAs and proteins in Arabidopsis seedlings. We demonstrate that these methods can be used in different organs of Arabidopsis seedlings as well as in other plant species. In order to achieve better reproducibility and higher throughput, we modified these protocols for automation to be performed by a liquid handling robot. In addition, we show that other procedures such as reporter enzyme assays and tissue clearing can be similarly automated. We present examples of application of our protocols including mRNA localisation and proteins and epitope tag (co)localisations which demonstrate that these methods provide reliable and versatile tools for expression, localisation and anatomical studies in plants.},
  author       = {Friml, Jirí and Benková, Eva and Mayer, Ulrike and Palme, Klaus and Muster, Gerhard},
  issn         = {1365-313X},
  journal      = {Plant Journal},
  number       = {1},
  pages        = {115 -- 124},
  publisher    = {Wiley},
  title        = {{Automated whole mount localisation techniques for plant seedlings}},
  doi          = {10.1046/j.1365-313X.2003.01705.x},
  volume       = {34},
  year         = {2003},
}