Biological significance of N-acetylglucosamine 6-sulfation

表达了三种N-乙酰氨基葡萄糖-6-磺基转移酶(GlcNAc6ST)，即GlcNAc6ST-1、GlcNAc6ST-2、GlcNAc6ST-3，并比较了特异性。 GlcNAc6ST-1和GlcNAc6ST-2作用于粘蛋白型核心2糖(GlcNAcβ1-6[Galβ1-3]GalNAc)并且两种酶之间没有显着差异。尽管已知GlcNAc6ST-2参与淋巴细胞归巢，但尚不清楚GlcNAc6ST-1是否发挥这样的作用。用 GlcNAc6ST-1 和岩藻糖基转移酶 VII 双转染的细胞诱导表达 L-选择素的细胞滚动。 GlcNAc6ST-3 仅作用于核心 2 糖。另一方面，只有 GlcNAc6ST-2 作用于核心 3 糖（GlcNAcβ1-3 GalNAc）。从这种特异性来看，GlcNAc6ST-2被认为是在粘液腺癌中新表达的酶，这一点通过RT-PCR分析得到了限制。我们制备了GlcNAc6ST-1基因缺陷的敲除小鼠。 Southern 和 Northern 印迹分析证实该小鼠完全缺乏 GlcNAc6ST-1。小鼠出生正常，未见明显异常。目前回交正在进行中，以便我们能够分析淋巴细胞归巢中可能存在的异常。使用杆状病毒系统在Tn5细胞中产生GilcNAc6ST-1作为fasion蛋白。纯化的重组酶可用于合成硫酸化寡糖和糖蛋白结合碳水化合物的硫酸化。

Three species of N-acetylglucosamine-6-sulfotransferases (GlcNAc6ST), namely GlcNAc6ST-1, GlcNAc6ST-2, GlcNAc6ST-3 were expressed and the specificities were compared. GlcNAc6ST-l as well as GlcNAc6ST-2 acted on mucin-type core 2 sugar (GlcNAcβ1-6[Galβ1-3]GalNAc) and there were not significant differences between the two enzymes. Although GlcNAc6ST-2 is known to be involved in lymphocyte homing, it is not clarified whether GlcNAc6ST-1 plays such a role. Cells doubly transfected with GlcNAc6ST-1 and fucosyltransferase VII induced roling of L-selectin-expressing cells. GlcNAc6ST-3 acted only on core 2 sugars. On the other hand, only GlcNAc6ST-2 acted on core 3 sugars (GlcNAcβ1-3 GalNAc). From this specificity, GlcNAc6ST-2 was considered to be the enzyme, which became newly expressed in mucinous adenocarcinoma, and this point was confined by RT-PCR analysis.We produced knockout mice deficient in the GlcNAc6ST-1 gene. That this mice completely lacked GlcNAc6ST-1 was confirmed by Southern and Northern blot analyses. The mice was born normally, and showed no apparent abnormality. Currently backcross is on the way, so that we are able to analyze possible abnormality in lymphocyte homing.GilcNAc6ST-1 was produced as fasion protein in Tn5 cells using the Baculovirus system. The purified recombinant enzyme was useful for synthesis of sulfated oligosaccharides and sulfation of glycoprotein-bound carbohydrates.