Ishida Hiroyasu, Togayachi Akira, Sakai Tokiko, Iwai Toshie, Hiruma Toru, Sato Takashi, Okubo Reiko, Inaba Niro, Kudo Takashi, Gotoh Masanori, Shoda Junichi, Tanaka Naomi, Narimatsu Hisashi
Glycogene Function Team, Research Center for Glycoscience, National Institute of Advanced Industrial Science and Technology, Central-2 OSL, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
FEBS Lett. 2005 Jan 3;579(1):71-8. doi: 10.1016/j.febslet.2004.11.037.
A new member of the UDP-N-acetylglucosamine: beta-galactose beta1,3-N-acetylglucosaminyltransferase (beta3Gn-T) family having the beta3-glycosyltransferase motifs was identified using an in silico method. This novel beta3Gn-T was cloned from a human colon cancer cell line and named beta3Gn-T8 based on its position in a phylogenetic tree and enzymatic activity. Beta3Gn-T8 transfers GlcNAc to the non-reducing terminus of the Galbeta1-4GlcNAc of tetraantennary N-glycan in vitro. HCT15 cells transfected with beta3Gn-T8 cDNA showed an increase in reactivity to both LEA and PHA-L4 in a flow cytometric analysis. These results indicated that beta3Gn-T8 is involved in the biosynthesis of poly-N-acetyllactosamine chains on tetraantennary (beta1,6-branched) N-glycan. In most of the colorectal cancer tissues examined, the level of beta3Gn-T8 transcript was significantly higher than in normal tissue. Beta3Gn-T8 could be an enzyme involved in the synthesis of poly-N-acetyllactosamine on beta1-6 branched N-glycans in colon cancer.
使用计算机模拟方法鉴定出UDP-N-乙酰葡糖胺：β-半乳糖β1,3-N-乙酰葡糖胺基转移酶（β3Gn-T）家族的一个具有β3-糖基转移酶基序的新成员。这种新型β3Gn-T是从人结肠癌细胞系中克隆出来的，并根据其在系统发育树中的位置和酶活性命名为β3Gn-T8。β3Gn-T8在体外将GlcNAc转移到四天线N-聚糖的Galβ1-4GlcNAc的非还原末端。用β3Gn-T8 cDNA转染的HCT15细胞在流式细胞术分析中对LEA和PHA-L4的反应性均增加。这些结果表明β3Gn-T8参与了四天线（β1,6-分支）N-聚糖上聚N-乙酰乳糖胺链的生物合成。在大多数检测的结直肠癌组织中，β3Gn-T8转录本水平显著高于正常组织。β3Gn-T8可能是一种参与结肠癌中β1-6分支N-聚糖上聚N-乙酰乳糖胺合成的酶。
