Nucleotide sugar interconversions and cell wall biosynthesis: how to bring the inside to the outside.
Plants possess a sophisticated sugar biosynthetic machinery comprising families of nucleotide sugar interconversion enzymes. Literature published in the past two years has made a major contribution to our knowledge of the enzymes and genes involved in the interconversion of nucleotide sugars that are required for cell wall biosynthesis, including UDP-L-rhamnose, UDP-D-galactose, UDP-D-glucuronic acid, UDP-D-xylose, UDP-D-apiose, UDP-L-arabinose, GDP-L-fucose and GDP-L-galactose. Indirect evidence suggests that enzyme activity is crudely regulated at the transcriptional level in a cell-type and differentiation-dependent manner. However, feedback inhibition and NAD(+)/NADH redox control, as well as the formation of complexes between differentially encoded isoforms and glycosyltransferases, might fine-tune cell wall matrix biosynthesis. I hypothesise that the control of nucleotide sugar interconversion enzymes regulates glycosylation patterns in response to developmental, metabolic and stress-related stimuli, thereby linking signalling with primary metabolism and the dynamics of the extracellular matrix.
Seifert
Georg J
GJ
John Innes Centre, Department of Cell and Developmental Biology, Colney, Norwich NR4 7UH, UK. georg.siefert@bbsrc.ac.uk
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006031:Glycosylation; D007527:Isoenzymes; D009702:Nucleoside Diphosphate Sugars / Q000378:metabolism*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D010944:Plants / Q000378:metabolism*
D007527:Isoenzymes; D009702:Nucleoside Diphosphate Sugars; D002244:Carbon; D010088:Oxidoreductases