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Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
12:06

Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines

Published on: November 25, 2017

Abnormalities caused by carbohydrate alterations in Ibeta6-N-acetylglucosaminyltransferase-deficient mice

Guo-Yun Chen1, Hisako Muramatsu, Mineo Kondo

  • 1Department of Biochemistry, Nagoya University School of Medicine, Japan.

Molecular and Cellular Biology
|August 19, 2005
PubMed

Ibeta6-N-acetylglucosaminyltransferase (IGnT) catalyzes the branching of poly-N-acetyllactosamine carbohydrate chains. In both humans and mice, three spliced forms of IGnT have been identified, and a common exon is present in all of them. We generated mice deficient in the common exon to understand the physiological function of poly-N-acetyllactosamine branching. IGnT activity was abolished in the stomach, kidney, bone marrow, and cerebellum of the deficient mice, while a low level of the activity persisted in the small intestine. Immunohistochemical analysis confirmed the loss of I antigen from the lung, stomach, and kidney. The deficient mice had reduced spontaneous locomotive activity. The number of peripheral blood lymphocytes was also reduced and renal function decreased in the deficient mice. Furthermore, in aged mice, vacuolization occurred in the kidney, and epidermoid cysts were frequently formed. However, cataracts did not develop earlier in the deficient mice. Decreased levels of lysosomal proteins, LAMP-2 and synaptotagmin VII, were found in the kidney of the deficient mice and correlated with renal abnormalities.

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