Environmental effects on phenotypic variation in plants

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Environmental effects on phenotypic variation in plants
Christopher Barrington1, Simon Engledow1, Hamad Sidiqqui1, Claude Becker2, David Schafer1,
Franziska Srocke1, Detlef Weigel2 and Jose Gutierrez-Marcos1
1School
of Life Sciences, University of Warwick, UK 2MPI for Developmental Biology, Tubingen, Germany
Background
Aim of the project
•  Plants are sessile organisms and as such need to
be able to rapidly adapt to their changing
environment to ensure their survival.
•  To investigate stress-induced phenotypic
variation in maize and identify the molecular
mechanisms responsible for their inheritance in
subsequent generations.
•  Environmental stress can influence plant growth
and cause changes in appearance (or phenotype)
that can be transmitted to the progeny,
sometimes remaining stable for several
generations. How this happens is not yet
understood.
Preliminary findings
•  Most phenotypic changes induced by heat stress
are not associated with changes in DNA
sequence, but in the way the DNA is chemically
modified and packaged in each cell, and are
known as “epigenetic changes”.
WT
Figure 1. Acquired resistance to stress in maize. Left
hand side, plants derived from seeds exposed to high
temperature. Right hand side, control plants derived from
seed propagated in standard growth conditions.
polIV
rdr2
Figure 2. Stress tolerance in maize is regulated
epigenetically. Left panel, maize mutant plants with defective
epigenetic machinery are more sensitive to heat stress when
compared to wild-type (WT). Right panel, representation of the
maize genome showing epigenetic changes induced by heat
stress (blue bars).
•  U n d e r s t a n d i n g h o w t h e s e s o - c a l l e d
environmentally-induced phenotypic traits are
generated and their mode of inheritance is
important, as they represent an unexplored
source of variation that can contribute to the
development and breeding of more robust crop
plants.
•  We have found that only a small fraction of the
identified epigenetic changes are inherited in
the next generation.
•  Maize plants represent a good model system to
study this phenomenon, as they can produce a
variety of recognizable traits in response to a
wide range of environmental conditions, such as
heat or drought, which they can remember.
•  To determine which genes are important in
regulating the inheritance of acquired
phenotypic variation induced by temperature
stress.
Future work
Warwick Crop Centre
www.warwick.ac.uk/go/wcc 
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