TY  - JOUR
A1  - Fujikura, Ushio
A1  - Elsaesser, Lore
A1  - Breuninger, Holger
A1  - Sanchez-Rodriguez, Clara
A1  - Ivakov, Alexander
A1  - Laux, Thomas
A1  - Findlay, Kim
A1  - Persson, Staffan
A1  - Lenhard, Michael
T1  - Atkinesin-13A modulates cell-wall synthesis and cell expansion in arabidopsis thaliana via the THESEUS1 pathway
JF  - PLoS Genetics : a peer-reviewed, open-access journal
N2  - Growth of plant organs relies on cell proliferation and expansion. While an increasingly detailed picture about the control of cell proliferation is emerging, our knowledge about the control of cell expansion remains more limited. We demonstrate the internal-motor kinesin AtKINESIN-13A (AtKIN13A) limits cell expansion and cell size in Arabidopsis thaliana, ion atkinl3a mutants forming larger petals with larger cells. The homolog, AtKINESIN-13B, also affects cell expansion and double mutants display growth, gametophytic and early embryonic defects, indicating a redundant role of he two genes. AtKIN13A is known to depolymerize microtubules and influence Golgi motility and distribution. Consistent his function, AtKIN13A interacts genetically with ANGUSTIFOLIA, encoding a regulator of Golgi dynamics. Reduced AtIGN13A activity alters cell wall structure as assessed by Fourier-transformed infrared-spectroscopy and triggers signalling he THESEUS1-dependent cell-wall integrity pathway, which in turn promotes the excess cell expansion in the atkinl3a mutant. Thus, our results indicate that the intracellular activity of AtKIN13A regulates cell expansion and wall architecture via THESEUS1, providing a compelling case of interplay between cell wall integrity sensing and expansion.
Y1  - 2014
U6  - https://doi.org/10.1371/journal.pgen.1004627
SN  - 1553-7390
SN  - 1553-7404
VL  - 10
IS  - 9
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - JOUR
A1  - Graf, Philipp
A1  - Dolzblasz, Alicja
A1  - Würschum, Tobias
A1  - Lenhard, Michael
A1  - Pfreundt, Ulrike
A1  - Laux, Thomas
T1  - MGOUN1 encodes an Arabidopsis type Ib DNA topoisomerase required in stem cell regulation and to maintain develpmentally regulated gene silencing
Y1  - 2010
SN  - 1040-4651
ER  - 
TY  - JOUR
A1  - Vi, Son Lang
A1  - Trost, Gerda
A1  - Lange, Peggy
A1  - Czesnick, Hjördis
A1  - Rao, Nishta
A1  - Lieber, Diana
A1  - Laux, Thomas
A1  - Gray, William M.
A1  - Manley, James L.
A1  - Groth, Detlef
A1  - Kappel, Christian
A1  - Lenhard, Michael
T1  - Target specificity among canonical nuclear poly(A) polymerases in plants
 modulates organ growth and pathogen response
JF  - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
 AMERICA
N2  - Polyadenylation of pre-mRNAs is critical for efficient nuclear export, stability, and translation of the mature mRNAs, and thus for gene expression. The bulk of pre-mRNAs are processed by canonical nuclear poly(A) polymerase (PAPS). Both vertebrate and higher-plant genomes encode more than one isoform of this enzyme, and these are coexpressed in different tissues. However, in neither case is it known whether the isoforms fulfill different functions or polyadenylate distinct subsets of pre-mRNAs. Here we show that the three canonical nuclear PAPS isoforms in Arabidopsis are functionally specialized owing to their evolutionarily divergent C-terminal domains. A strong loss-of-function mutation in PAPS1 causes a male gametophytic defect, whereas a weak allele leads to reduced leaf growth that results in part from a constitutive pathogen response. By contrast, plants lacking both PAPS2 and PAPS4 function are viable with wild-type leaf growth. Polyadenylation of SMALL AUXIN UP RNA (SAUR) mRNAs depends specifically on PAPS1 function. The resulting reduction in SAUR activity in paps1 mutants contributes to their reduced leaf growth, providing a causal link between polyadenylation of specific pre-mRNAs by a particular PAPS isoform and plant growth. This suggests the existence of an additional layer of regulation in plant and possibly vertebrate gene expression, whereby the relative activities of canonical nuclear PAPS isoforms control de novo synthesized poly(A) tail length and hence expression of specific subsets of mRNAs.
Y1  - 2013
U6  - https://doi.org/10.1073/pnas.1303967110
SN  - 0027-8424
VL  - 110
IS  - 34
SP  - 13994
EP  - 13999
PB  - NATL ACAD SCIENCES
CY  - WASHINGTON
ER  -