Fructokinase is required for carbon partitioning to cellulose in aspen wood

Plant J. 2012 Jun;70(6):967-77. doi: 10.1111/j.1365-313X.2012.04929.x. Epub 2012 Apr 3.


Sucrose is the main transported form of carbon in several plant species, including Populus species. Sucrose metabolism in developing wood has therefore a central role in carbon partitioning to stem biomass. Half of the sucrose-derived carbon is in the form of fructose, but metabolism of fructose has received little attention as a factor in carbon partitioning to walls of wood cells. We show that RNAi-mediated reduction of FRK2 activity in developing wood of hybrid aspen (Populus tremula × tremuloides) led to the accumulation of soluble neutral sugars and a decrease in hexose phosphates and UDP-glucose, indicating that carbon flux to cell-wall polysaccharide precursors is decreased. Reduced FRK2 activity also led to thinner fiber cell walls with a reduction in the proportion of cellulose. No pleiotropic effects on stem height or diameter were observed. The results establish a central role for FRK2 activity in carbon flux to wood cellulose.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbohydrate Metabolism
  • Carbon / metabolism*
  • Cell Wall / metabolism
  • Cellulose / metabolism*
  • Fructokinases / genetics
  • Fructokinases / metabolism*
  • Gene Expression Regulation, Plant
  • Isoenzymes / genetics
  • Isoenzymes / metabolism
  • Metabolome
  • Oligonucleotide Array Sequence Analysis
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Stems / metabolism
  • Populus / enzymology*
  • Populus / genetics
  • RNA Interference
  • Sucrose / metabolism
  • Wood / metabolism*


  • Isoenzymes
  • Plant Proteins
  • Sucrose
  • Carbon
  • Cellulose
  • Fructokinases
  • fructokinase