The Arabidopsis SUCROSE UNCOUPLED-6 gene is identical to ABSCISIC ACID INSENSITIVE-4: involvement of abscisic acid in sugar responses.
In plants, sugars act as signalling molecules that control many aspects of metabolism and development. Arabidopsis plants homozygous for the recessive sucrose uncoupled-6 (sun6) mutation show a reduced sensitivity to sugars for processes such as photosynthesis, gene expression and germination. The sun6 mutant is insensitive to sugars that are substrates for hexokinase, suggesting that SUN6 might play a role in hexokinase-dependent sugar responses. The SUN6 gene was cloned by transposon tagging and analysis showed it to be identical to the previously described ABSCISIC ACID INSENSITIVE-4 (ABI4) gene. Our analysis suggests the involvement of abscisic acid and components of the abscisic acid signal transduction cascade in a hexokinase-dependent sugar response pathway. During the plant life cycle, SUN6/ABI4 may be involved in controlling metabolite availability in an abscisic acid- and sugar-dependent way.
Huijser
C
C
Department of Molecular Plant Physiology and; Department of Molecular Genetics, University of Utrecht, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Kortstee
A
A
Pego
J
J
Weisbeek
P
P
Wisman
E
E
Smeekens
S
S
D000040:Abscisic Acid / Q000502:physiology*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D017343:Genes, Plant; D006720:Homozygote; D015398:Signal Transduction
D000040:Abscisic Acid