Abstract:
:Eukaryotic cells require N-linked carbohydrates for survival. However, the biosynthetic intermediate Man5GlcNAc2Asn, in place of mature N-linked structures, allows glycoprotein synthesis and somatic cell growth to proceed normally. To determine whether the same would be true in a complex biological situation, the gene Mgat-1 was disrupted by homologous recombination in embryonic stem cells and transmitted to the germ line. The Mgat-1 gene encodes N-acetylglucosaminyltransferase I [GlcNAc-TI; alpha-1,3-mannosyl-glycoprotein beta-1,2-N-acetylglucosaminyltransferase; UDP-N-acetyl-D-glucosamine:glycoprotein (N-acetyl-D-glucosamine to alpha-D-mannosyl-1,3-(R1)-beta-D-mannosyl-R2) beta-1,2-N-acetyl-D-glucosaminyltransferase, EC 2.4.1.101], the transferase that initiates synthesis of hybrid and complex N-linked carbohydrates from Man5GlcNAc2Asn. Mice lacking GlcNAc-TI activity did not survive to term. Biochemical and morphological analyses of embryos from 8.5 to 13.5 days of gestation showed that Mgat-1-/-embryos are developmentally retarded, most noticeably in neural tissue, and die between 9.5 and 10.5 days of development.
journal_name
Proc Natl Acad Sci U S Aauthors
Ioffe E,Stanley Pdoi
10.1073/pnas.91.2.728subject
Has Abstractpub_date
1994-01-18 00:00:00pages
728-32issue
2eissn
0027-8424issn
1091-6490journal_volume
91pub_type
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