Edinburgh, Scotland, United Kingdom - TAIR

Divide et impera – cell division in the root and
its control through ABA
Abscisic acid (ABA) is primarily known as a stress hormone that relays the plants
responses to environmental signals such as drought, salt stress or cold.
Increases in ABA concentration lead to inhibition of root growth but it is unclear
what the underlying cellular and molecular mechanisms are. Detailed analysis of
root growth and cell division markers revealed that ABA regulates growth of
primary and lateral roots by influencing cell division rates. Further analysis of
cell cycle component mutants provide the first evidence for a molecular
mechanism connecting the ABA signal with the cell cycle machinery.
We are also interested where in the root the ABA signal is perceived and have
used a transactivation approach to investigate whether any root tissue is
particularly important for ABA signal perception. Results will be presented that
show that it is indeed possible to render the whole root ABA insensitive by
blocking ABA perception in one cell file. Cell division rates in the root apical
meristem have to be orchestrated between cells of different identities, sizes and
shapes and the wider implications of this finding on the control of cell division in
the root will be discussed.
In summary, we show some of the mechanisms by which ABA integrates
environmental responses into the root developmental growth program and thus
shapes root growth.
86
C35
Thursday 15:45 - 16:00
Plant Growth Regulators
Daniela Dietrich1
Susana Ubeda-Tomas1
Rishikesh Bhalerao2
Malcolm Bennett1
1Centre for Plant
Integrative Biology
University of Nottingham
Sutton Bonington Campus
Loughborough
LE12 5RD
UK
2Umeå Plant Science
Centre
Department of Forest
Genetics and Plant
Physiology
SLU
SE-901 83 Umeå
Sweden