EVOLUTION AND DIVERSITY OF EUKARYOTIC GLYCOSYLATION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 虽然酿酒酵母一直是人类N-和O-连接的糖基化和GPI-锚合成的良好模型，但蛋白质糖基化的大部分进化和多样性存在于高度不同的原生生物之间。动质体糖基化(如锥虫sp.和利什曼原虫(Leishmania sp.)已被广泛研究，但对微嗜气性原生生物(阴道毛滴虫、蓝氏贾第鞭毛虫(Gi)和溶组织内阿米巴(Eh))的糖基化研究还不够深入。预测总蛋白质(蛋白质组)的全基因组序列现在可用于所有这些原生生物物种。基于我们的生物信息学/实验方法的真核细胞糖基化多样性的初步证据预测，Eh和Tv可以产生缩写的二十二醇连接的N-糖链前体。 初步实验证明，Eh和Tv确实合成了缩合的二羟苯二酚连接的N-葡聚糖前体。因此，被截断的前体很可能是任何后续修改的起点。然而，反向遗传学可能无法预测针对特定抗议利基的修饰，因此，将进行结构研究，以确定寡糖是否被额外的高尔基或高尔基样修饰所修饰，或者如果它们像在锥体中发现的那样被简单地截断。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. While Saccharomyces cerevisiae has been a good model for human N- and O-linked glycosylation and GPI-anchor synthesis, most of the evolution and diversity in protein glycosylation exists among deeply divergent protists. Glycosylation of kinetoplastids (e.g. Trypanosoma sp. and Leishmania sp.) has been extensively studied, but glycosylation of microaerophilic protists (Trichomonas vaginalis, Giardia lamblia (GI), and Entamoeba histolytica (Eh) are not well studied. Whole genome sequences that predict the total proteins (proteome) are now available for all of these protist species. Preliminary evidence of the diversity of eukaryotic glycosylation based upon our bioinformatics/ experimental approach predict that Eh and Tv make abbreviated dolichol-linked N-glycan precursors. Preliminary experiments demonstrate that Eh and Tv do, indeed, synthesize abbreviated dolichol-linked N-glycan precursors. Therefore, the truncated precursors will likely be the starting point for any subsequent modifications. However, reverse genetics may not predict modifications that are specific to the niche of a given protest and, therefore, structural studies will be conducted to determine if the oligosaccharides are modified by additional Golgi or Golgi-like modifications or if they are simply truncated as found in, Trypanosomes.