Arabidopsis and forestry

[Chris Somerville]

Last summer I reviewed a large grant application by a group of 
Swedish scientists who proposed to create a center for forest 
biotechnology in which a large proportion of the funding would be 
devoted to research on Arabidopsis.   This struck me as very forward 
looking and, therefore,  I asked Goran Sandberg the PI of the Swedish 
consortium to write the following short explanation of their rationale for public 
release (I have edited it slightly).  
Chris Somerville
******************************
  Strategy of  the Swedish Centre for Forest Biotechnology and
  Chemistry
  
  The importance of the Swedish forest industry to the Swedish
  economy can not be understated. Wood and paper products
  account for more than 50 % of Swedish net exports generating
  57 billion SEK per annum. The success of this industry  has
  traditionally been based  to a certain extent on the quality
  of the forest management techniques, but mainly on the use of
  advanced technology in pulp and paper processes
     The Centre for  Forest Biotechnology and Chemistry was
  created to  enhance collaboration between biologists studying
  the growth and development of forest trees and  chemists
  working on the processing of the raw biological material. The
  basic strategy is to create technically advanced facilities
  for characterisation of wood and fibres (like NMR, mass
  spectrometry and NIR) that can be used on  new raw materials
  developed by  the biologists.  The biological modifications
  could of course be done by traditional breeding, but in  the
  time frame given for this project, the use of genetic
  engineering is essential.
     Sweden has several strong groups working with forest
  biotechnology. The problem is however that even if we are able
  to create the best groups in the world working with  forest
  biotechnology, they will still only be of average quality in
  comparison with general plant biotechnology because trees are
  difficult organisms, they grow slowly and are sometimes 
  difficult to handle.
     At the time when we developed the strategy for this
  centre, the obvious solution was to attract the best groups
  working with other plant systems and convince them that they
  should  start up projects on trees. Our pragmatic view was
  that  if we can get  solid  groups working with basic science
  into this centre, the  problem with recruiting the best
  scientists to work on problems n forestry would be solved by
  itself. The idea was that  the students should work on one
  tree system, in our case poplar, but would also be allowed to
  perform necessary work on  Arabidopsis. This was at that time
  an obvious  compromise since  although the trees in many ways
  have an unique biology that will  be the basis for  new and
  interesting lines of research, many aspects of their
  physiology can be more easily investigated  in a model system
  like Arabidopsis.
     This concept has completely changed during the past year.
  What was started as a compromise designed to create a good
  research environment has now developed into fundamental 
  strategy for the whole centre. The idea to define the
  biological question in a tree and to investigate it in
  Arabidopsis is not of course unique. The technical and genetic
  advantages of Arabidopsis are obvious.  However, during the
  last year,  several striking examples illustrating both the
  common genetic controls, and the interesting divergence's,
  between Arabidopsis  and trees  have been demonstrated. We
  have been involved in two studies, for instance, in which
  genes isolated from Arabidopsis have been proven to have
  essentially the same function in trees, but with even stronger
  phenotypic effects. The first example is LEAFY -which is
  involved in meristem identity in Arabidopsis. Poplar usually
  takes 3 - 5 years to flower, but when the Arabidopsi gene is
  expressed in the tree, it flowers in the tissue culture after
  only 6 -8 weeks (Weigel and Nilsson;Nature-95). 
     The second example is expression of phytochrome  A and B
  genes from Arabidopsis  in poplar. It is well known that these
  genes are involved in  daylength regulation but nothing is
  really known about how  important they are in forest species. 
  Cessation of growth at the appropriate time is critical for
  trees growing at high latitudes . The organisms must stop
  their  growth and prepare for winter early since they have to
  survive for many years and can not take any chances with 
  early chilling. This is a common basis for  forest tree
  breeding in which provinanses are moved northwards from their
  point of origin to prolong the growing season. Poplar plants
  overexpressing the phytochrome genes from annuals completely
  lose their ability to  sense the light signal and therefore do
  not respond to it.  The poplar line that we are using  has a
  critical night length of 8 hours meaning that if the night
  becomes longer than this, the plant prepares for winter. The
  phy  poplars  continue to grow even if they get 16 hours of
  night. 
     Both these examples will in the future have a practical
  value in forestry and they are both based on  work done in
  Arabidopsis. Without the Arabidopsis data, it would have taken
  another 5- 10 years to get this information out of the trees.
     The link between Arabidopsis and trees is now well
  established in Europe, Several other projects are currently 
  discussed that are based on this concept:
     Wood formation: Isolation of Arabidopsis mutants with
  altered floem and/or xylem formation.
     Branching: Isolation of Arabidopsis mutants  with altered
  branching through effects on the auxin/cytokinin ratios.
     Shoot elongation: Cloning of Arabidopsis genes involved
  in the regulation of GA homeostasis
     Oxidative stress: Isolation of Arabidopsis mutants with
  altered sensitivity to this stress factor.
     In all cases, the identified genes from Arabidopsis  will
  be expressed in poplar, and if the show interesting phenotypes
  , the genes will be cloned from a tree species
     There are in conclusion very strong practical reasons for
  linking research into forest trees and Arabidopsis. We
  therefore cordially invite any groups worldwide, who have
  identified genes in Arabidopsis which may yield interesting
  data if expressed in a tree species to contact us, with a view
  to mutually beneficial collaboration.
  
  Goran Sandberg
  Director for Centre of Forest Biotechnology and Chemistry