@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{6262,
  abstract     = {Gravitropism is an adaptive response that orients plant growth parallel to the gravity vector. Asymmetric
distribution of the phytohormone auxin is a necessary prerequisite to the tropic bending both in roots and
shoots. During hypocotyl gravitropic response, the PIN3 auxin transporter polarizes within gravity-sensing
cells to redirect intercellular auxin fluxes. First gravity-induced PIN3 polarization to the bottom cell mem-
branes leads to the auxin accumulation at the lower side of the organ, initiating bending and, later, auxin
feedback-mediated repolarization restores symmetric auxin distribution to terminate bending. Here, we per-
formed a forward genetic screen to identify regulators of both PIN3 polarization events during gravitropic
response. We searched for mutants with defective PIN3 polarizations based on easy-to-score morphological
outputs of decreased or increased gravity-induced hypocotyl bending. We identified the number of
hypocotyl reduced bending (hrb) and hypocotyl hyperbending (hhb) mutants, revealing that reduced bending corre-
lated typically with defective gravity-induced PIN3 relocation whereas all analyzed hhb mutants showed
defects in the second, auxin-mediated PIN3 relocation. Next-generation sequencing-aided mutation map-
ping identified several candidate genes, including SCARECROW and ACTIN2, revealing roles of endodermis
specification and actin cytoskeleton in the respective gravity- and auxin-induced PIN polarization events.
The hypocotyl gravitropism screen thus promises to provide novel insights into mechanisms underlying cell
polarity and plant adaptive development.},
  author       = {Rakusová, Hana and Han, Huibin and Valošek, Petr and Friml, Jiří},
  issn         = {1365-313x},
  journal      = {The Plant Journal},
  number       = {6},
  pages        = {1048--1059},
  publisher    = {Wiley},
  title        = {{Genetic screen for factors mediating PIN polarization in gravistimulated Arabidopsis thaliana hypocotyls}},
  doi          = {10.1111/tpj.14301},
  volume       = {98},
  year         = {2019},
}