Encodes a novel protein involved in ascorbate biosynthesis, which was shown to catalyze the transfer of GMP from GDP-galactose to a variety of hexose-1-phosphate acceptors. Recessive mutation has a reduced amount of vitamin C, lower level of non-photochemical quenching, and reduced rate of conversion of violaxanthin to zeaxanthin in high light.
At4g26850 codes for GDP-L-galactose-hexose-1-phosphate guanyltransferase which catalyzing the transfer of GMP from GDP-L-galactose to a hexose-1-P, most likely D-mannose-1-phosphate in vivo. [galactose guanyltransferase]
and interoperation is funded by 
