HEPARAN SULFATE BIOSYNTHETIC FEEDBACKS AND EXTRACELLULAR SULFATASE EXPRESSION

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 硫是修饰细胞表面和细胞外基质中硫酸乙酰肝素（HS）链的细胞外内硫酸酯酶家族。 它们在HS链中葡萄糖胺残基子集的6-O-位置释放硫酸根基团。 Sulf酶的活性用于增强生长因子（包括GDNF、BMP、Shh和Wnt）的活性，并降低FGF 2、HP-EGF、HGF和TGF-β的活性。 由于这些活动，并根据上下文，硫已被观察到作为致癌效应和肿瘤抑制剂。 Sulf活性似乎诱导生物合成酶表达的变化，导致表达的HS结构的变化，其不一定反映直接Sulf酶活性。 因此，Sulf活性对细胞表型的影响是复杂的。 本工作的目的是（1）确定小鼠胚胎成纤维细胞中HS结构表型作为在HS二糖和寡糖水平上的Sulf酶敲除的函数。 将这些结果与使用重组Sulf酶对纯化HS获得的结果进行比较。 最新进展： 我们已经发表了两篇关于HS结构表型的合作论文，这些表型与Sulf基因敲除小鼠中的精原干细胞龛（1）和肾小球滤过屏障（2）相关。 1. Langsdorf，A.，Schumacher，V.，施，X.，Tran，T.，Zaia，J.，Jain，S.，Taglienti，M.，Kreidberg，J. A.，好吧A和Ai，X.等人（2010）精原干细胞龛中硫的表达调节和功能，糖生物学21，152-161。 2. Schumacher，V.，Schlotzer-Schrehardt，美国，Karumanchi，S.一、施，X.，Zaia，J.，Jeruschke，S.，Zhang，D.，帕文施塔特，H.，Drenckhan，A.，阿曼，K.，Ng，C.，Hartwig，S.，Ng，K.- H、何杰，Kreidberg，J. A.，Taglienti，M.，Royer-Pokora，B.，和Ai，X.（2011）WT 1调节Sulf表达对维持肾小球滤过屏障至关重要，美国肾脏病学会杂志接受2/22/11。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Sulfs are a family of extracellular endosulfatases that modify heparan sulfate (HS) chains at cell surfaces and in extracellular matrices. They release sulfate groups at the 6-O-position of a subset of glucosamine residues in HS chains. The activity of Sulf enzymes serves to potentiate activities of growth factors including GDNF, BMP, Shh, and Wnt and to reduce activities of FGF2, HP-EGF, HGF, and TGF-¿. As a result of these activities and depending on the context, Sulfs have been observed to serve as oncogenic effectors and as tumor suppressors. Sulf activities appear to induce changes in expression of biosynthetic enzymes, resulting in changes in expressed HS structure that do not necessary reflect the direct Sulf enzymatic activity. As a result, the influences of Sulf activity on cellular phenotype are complex. The goals of this work are to (1) define the HS structural phenotype in mouse embryonic fibroblast cells as a function of Sulf enzyme knockout at both the HS disaccharide and oligosaccharide levels. These results will be compared against those obtained using recombinant Sulf enzymes on purified HS. Progress update: We have published two collaborative papers on the structural phenotypes of HS related to the spermatogonal stem cell niche (1) and the glomerular filtration barrier (2) in Sulf knockout mice. 1. Langsdorf, A., Schumacher, V., Shi, X., Tran, T., Zaia, J., Jain, S., Taglienti, M., Kreidberg, J. A., Fine, A., and Ai, X. (2010) Expression regulation and function of Sulfs in the spermatogonial stem cell niche, Glycobiology 21, 152-161. 2. Schumacher, V., Schlotzer-Schrehardt, U., Karumanchi, S. A., Shi, X., Zaia, J., Jeruschke, S., Zhang, D., Pavenstaedt, H., Drenckhan, A., Amann, K., Ng, C., Hartwig, S., Ng, K.-H., Ho, J., Kreidberg, J. A., Taglienti, M., Royer-Pokora, B., and Ai, X. (2011) WT1 regulation of Sulf expression is crucial to maintaining the glomerular filtration barrier, Journal of the American Society for Nephrology Accepted 2/22/11.