---
_id: '203'
abstract:
- lang: eng
text: Asymmetric auxin distribution is instrumental for the differential growth
that causes organ bending on tropic stimuli and curvatures during plant development.
Local differences in auxin concentrations are achieved mainly by polarized cellular
distribution of PIN auxin transporters, but whether other mechanisms involving
auxin homeostasis are also relevant for the formation of auxin gradients is not
clear. Here we show that auxin methylation is required for asymmetric auxin distribution
across the hypocotyl, particularly during its response to gravity. We found that
loss-of-function mutants in Arabidopsis IAA CARBOXYL METHYLTRANSFERASE1 (IAMT1)
prematurely unfold the apical hook, and that their hypocotyls are impaired in
gravitropic reorientation. This defect is linked to an auxin-dependent increase
in PIN gene expression, leading to an increased polar auxin transport and lack
of asymmetric distribution of PIN3 in the iamt1 mutant. Gravitropic reorientation
in the iamt1 mutant could be restored with either endodermis-specific expression
of IAMT1 or partial inhibition of polar auxin transport, which also results in
normal PIN gene expression levels. We propose that IAA methylation is necessary
in gravity-sensing cells to restrict polar auxin transport within the range of
auxin levels that allow for differential responses.
article_processing_charge: No
author:
- first_name: Mohamad
full_name: Abbas, Mohamad
id: 47E8FC1C-F248-11E8-B48F-1D18A9856A87
last_name: Abbas
- first_name: García J
full_name: Hernández, García J
last_name: Hernández
- first_name: Stephan
full_name: Pollmann, Stephan
last_name: Pollmann
- first_name: Sophia L
full_name: Samodelov, Sophia L
last_name: Samodelov
- first_name: Martina
full_name: Kolb, Martina
last_name: Kolb
- first_name: Jirí
full_name: Friml, Jirí
id: 4159519E-F248-11E8-B48F-1D18A9856A87
last_name: Friml
orcid: 0000-0002-8302-7596
- first_name: Ulrich Z
full_name: Hammes, Ulrich Z
last_name: Hammes
- first_name: Matias D
full_name: Zurbriggen, Matias D
last_name: Zurbriggen
- first_name: Miguel
full_name: Blázquez, Miguel
last_name: Blázquez
- first_name: David
full_name: Alabadí, David
last_name: Alabadí
citation:
ama: Abbas M, Hernández GJ, Pollmann S, et al. Auxin methylation is required for
differential growth in Arabidopsis. PNAS. 2018;115(26):6864-6869. doi:10.1073/pnas.1806565115
apa: Abbas, M., Hernández, G. J., Pollmann, S., Samodelov, S. L., Kolb, M., Friml,
J., … Alabadí, D. (2018). Auxin methylation is required for differential growth
in Arabidopsis. PNAS. National Academy of Sciences. https://doi.org/10.1073/pnas.1806565115
chicago: Abbas, Mohamad, García J Hernández, Stephan Pollmann, Sophia L Samodelov,
Martina Kolb, Jiří Friml, Ulrich Z Hammes, Matias D Zurbriggen, Miguel Blázquez,
and David Alabadí. “Auxin Methylation Is Required for Differential Growth in Arabidopsis.”
PNAS. National Academy of Sciences, 2018. https://doi.org/10.1073/pnas.1806565115.
ieee: M. Abbas et al., “Auxin methylation is required for differential growth
in Arabidopsis,” PNAS, vol. 115, no. 26. National Academy of Sciences,
pp. 6864–6869, 2018.
ista: Abbas M, Hernández GJ, Pollmann S, Samodelov SL, Kolb M, Friml J, Hammes UZ,
Zurbriggen MD, Blázquez M, Alabadí D. 2018. Auxin methylation is required for
differential growth in Arabidopsis. PNAS. 115(26), 6864–6869.
mla: Abbas, Mohamad, et al. “Auxin Methylation Is Required for Differential Growth
in Arabidopsis.” PNAS, vol. 115, no. 26, National Academy of Sciences,
2018, pp. 6864–69, doi:10.1073/pnas.1806565115.
short: M. Abbas, G.J. Hernández, S. Pollmann, S.L. Samodelov, M. Kolb, J. Friml,
U.Z. Hammes, M.D. Zurbriggen, M. Blázquez, D. Alabadí, PNAS 115 (2018) 6864–6869.
date_created: 2018-12-11T11:45:11Z
date_published: 2018-06-26T00:00:00Z
date_updated: 2025-05-07T11:12:32Z
day: '26'
department:
- _id: JiFr
doi: 10.1073/pnas.1806565115
ec_funded: 1
external_id:
isi:
- '000436245000096'
intvolume: ' 115'
isi: 1
issue: '26'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: http://eprints.nottingham.ac.uk/52388/
month: '06'
oa: 1
oa_version: None
page: 6864-6869
project:
- _id: 25716A02-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '282300'
name: Polarity and subcellular dynamics in plants
publication: PNAS
publication_status: published
publisher: National Academy of Sciences
publist_id: '7710'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Auxin methylation is required for differential growth in Arabidopsis
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 115
year: '2018'
...
---
_id: '1212'
abstract:
- lang: eng
text: 'Plants adjust their growth according to gravity. Gravitropism involves gravity
perception, signal transduction, and asymmetric growth response, with organ bending
as a consequence [1]. Asymmetric growth results from the asymmetric distribution
of the plant-specific signaling molecule auxin [2] that is generated by lateral
transport, mediated in the hypocotyl predominantly by the auxin transporter PIN-FORMED3
(PIN3) [3–5]. Gravity stimulation polarizes PIN3 to the bottom sides of endodermal
cells, correlating with increased auxin accumulation in adjacent tissues at the
lower side of the stimulated organ, where auxin induces cell elongation and, hence,
organ bending. A curvature response allows the hypocotyl to resume straight growth
at a defined angle [6], implying that at some point auxin symmetry is restored
to prevent overbending. Here, we present initial insights into cellular and molecular
mechanisms that lead to the termination of the tropic response. We identified
an auxin feedback on PIN3 polarization as underlying mechanism that restores symmetry
of the PIN3-dependent auxin flow. Thus, two mechanistically distinct PIN3 polarization
events redirect auxin fluxes at different time points of the gravity response:
first, gravity-mediated redirection of PIN3-mediated auxin flow toward the lower
hypocotyl side, where auxin gradually accumulates and promotes growth, and later
PIN3 polarization to the opposite cell side, depleting this auxin maximum to end
the bending. Accordingly, genetic or pharmacological interference with the late
PIN3 polarization prevents termination of the response and leads to hypocotyl
overbending. This observation reveals a role of auxin feedback on PIN polarity
in the termination of the tropic response. © 2016 Elsevier Ltd'
acknowledgement: "We thank Dr. Jie Li (Key Laboratory of Plant Molecular Physiology,
Chinese Academy of Science, China) for the pPIN3::PIN3-GFP/DII::VENUS line and Martine
De Cock for help in preparing the manuscript. This work was supported by the European
Research Council (project ERC-2011-StG-20101109-PSDP), by the Czech Science Foundation
GAČR (GA13-40637S) to J.F., and by the Ministry of Education, Youth and Sports of
the Czech Republic under the project CEITEC 2020 (LQ1601) to H.S.R. H.R. is indebted
to the Agency for Innovation by Science and Technology (IWT) for a predoctoral fellowship.\r\n"
author:
- first_name: Hana
full_name: Rakusová, Hana
last_name: Rakusová
- first_name: Mohamad
full_name: Abbas, Mohamad
id: 47E8FC1C-F248-11E8-B48F-1D18A9856A87
last_name: Abbas
- first_name: Huibin
full_name: Han, Huibin
id: 31435098-F248-11E8-B48F-1D18A9856A87
last_name: Han
- first_name: Siyuan
full_name: Song, Siyuan
last_name: Song
- first_name: Hélène
full_name: Robert, Hélène
last_name: Robert
- first_name: Jirí
full_name: Friml, Jirí
id: 4159519E-F248-11E8-B48F-1D18A9856A87
last_name: Friml
orcid: 0000-0002-8302-7596
citation:
ama: Rakusová H, Abbas M, Han H, Song S, Robert H, Friml J. Termination of shoot
gravitropic responses by auxin feedback on PIN3 polarity. Current Biology.
2016;26(22):3026-3032. doi:10.1016/j.cub.2016.08.067
apa: Rakusová, H., Abbas, M., Han, H., Song, S., Robert, H., & Friml, J. (2016).
Termination of shoot gravitropic responses by auxin feedback on PIN3 polarity.
Current Biology. Cell Press. https://doi.org/10.1016/j.cub.2016.08.067
chicago: Rakusová, Hana, Mohamad Abbas, Huibin Han, Siyuan Song, Hélène Robert,
and Jiří Friml. “Termination of Shoot Gravitropic Responses by Auxin Feedback
on PIN3 Polarity.” Current Biology. Cell Press, 2016. https://doi.org/10.1016/j.cub.2016.08.067.
ieee: H. Rakusová, M. Abbas, H. Han, S. Song, H. Robert, and J. Friml, “Termination
of shoot gravitropic responses by auxin feedback on PIN3 polarity,” Current
Biology, vol. 26, no. 22. Cell Press, pp. 3026–3032, 2016.
ista: Rakusová H, Abbas M, Han H, Song S, Robert H, Friml J. 2016. Termination of
shoot gravitropic responses by auxin feedback on PIN3 polarity. Current Biology.
26(22), 3026–3032.
mla: Rakusová, Hana, et al. “Termination of Shoot Gravitropic Responses by Auxin
Feedback on PIN3 Polarity.” Current Biology, vol. 26, no. 22, Cell Press,
2016, pp. 3026–32, doi:10.1016/j.cub.2016.08.067.
short: H. Rakusová, M. Abbas, H. Han, S. Song, H. Robert, J. Friml, Current Biology
26 (2016) 3026–3032.
date_created: 2018-12-11T11:50:44Z
date_published: 2016-11-21T00:00:00Z
date_updated: 2021-01-12T06:49:08Z
day: '21'
ddc:
- '581'
department:
- _id: JiFr
doi: 10.1016/j.cub.2016.08.067
ec_funded: 1
file:
- access_level: open_access
checksum: 79ed2498185a027cf51a8f88100379e6
content_type: application/pdf
creator: system
date_created: 2018-12-12T10:09:33Z
date_updated: 2020-07-14T12:44:39Z
file_id: '4757'
file_name: IST-2018-1008-v1+1_Rakusova_CurrBiol_2016_proof.pdf
file_size: 5391923
relation: main_file
file_date_updated: 2020-07-14T12:44:39Z
has_accepted_license: '1'
intvolume: ' 26'
issue: '22'
language:
- iso: eng
month: '11'
oa: 1
oa_version: Submitted Version
page: 3026 - 3032
project:
- _id: 25716A02-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '282300'
name: Polarity and subcellular dynamics in plants
publication: Current Biology
publication_status: published
publisher: Cell Press
publist_id: '6138'
pubrep_id: '1008'
quality_controlled: '1'
scopus_import: 1
status: public
title: Termination of shoot gravitropic responses by auxin feedback on PIN3 polarity
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 26
year: '2016'
...