SWAP & SR PROTEIN REGULATION OF ALTERNATIVE SPLICING

糖基转移酶似乎是高度特异性的， 结构特异性主要由寡糖保留。 Tbus，从有限的研究描述，它似乎是一个残留的 位置和连接遵循特定的模式， 异质性表示缺少模式完成。 的基础 了解聚糖的功能意义是一个详细的 特定场地结构分析。 为了解决第一个问题，我们 已经对蛋白质进行了聚糖分子量分析 构建体LFA 3和IgG。 LFA 3 TIP是用第一个 淋巴细胞功能相关分子3胞外区 在一个实施方案中，本发明提供了与人IgGl的铰链区、CH 2区和CH 3区融合的LFA 3。 通过N-连接聚糖的糖苷内切酶释放获得分析， 甲基化和使用电喷雾电离质谱的提取 光谱法和碰撞诱导分解（CID）。 为了 确定神经氨酰键（例如，2-+3，vs. 2-+6），乳糖基 延伸和三触角分支位置，氧化，还原， 和甲基化（ORM）在释放的聚糖上进行， ES-MS和CID。 酶释放的初步评估 策略，甲基化和提取通过ESI MS进行评价， 样品LFA 3-A、LFA 3-A1、LFA 3113和LFA 3，LFA 3-A中的每一种样品的μ g （TS 95 R 0 275）和LFA 3-B（TS 95 R 0 275）。 这些研究表明， 终止糖并不是随机分布在各种 触角，但发生优先重视特定的 N-乙酰乳糖胺残基。 所有化合物的该ESI MS质量曲线 结构可以是最具信息性的，并作为第一层次的 结构调查，类似于碳水化合物成分分析。

Glycosyltransferases appear to be highly specific and the structural specificity is primarily retained by the oligosaccharide. Tbus, from the limited studies described, it appears that a residue's position and linkage follows a specific pattern and glycoprotein heterogeneity represents a lack of pattern completion. Fundamental to understanding glycan functional significance is a detailed site-specific structural analysis. To approach this first problem, we have undertaken glycan molecular weight profiles on the protein constructs LFA3 and IgG. LFA3TIP wasconstructed with the first extracellular domain of lymphocyte function-associated molecule 3 (LFA3) fused to the hinge, CH2, and CH3 regions of a human IgGl. Analyses were acquired by endoglycosidase release of N-linked glycans, methylation, and extraction using electrospray ionization mass spectrometry and collision-induced decomposition (CID). In order to determine neuraminyl linkages (e.g., 2-+3, vs. 2-+6), lactosyl extensions, and triantennary branched positions, oxidation, reduction, and methylation (ORM) were carried out on the released glycans prior to ES-MS and CID. Preliminary assessment of enzymatic release strategies, methylation and extraction were evaluated by ESI MS on samples LFA3-A, LFA3-Al, LFA3113, and LFA3 pg of sample each of LFA3-A (TS95RO275) and LFA3-B (TS95RO275). These studies have shown that the terminating sugars are not randomly distributed over the various antennae, but occur preferentially attached to specific N-acetyllactosamine residues. This ESI MS mass profile of all structures can be most informative and serves as a first level of structural inquiry, akin to carbohydrate composition analysis.