Site-specific O-GlcNAc MAbs: New Tools for Glycoproteomics

描述(申请人提供)：由单一的β-N-乙酰-D-氨基葡萄糖部分(O-GlcNAc)对核蛋白和细胞质蛋白的丝氨酸和苏氨酸进行O-糖基化是一种普遍存在的翻译后修饰，高度动态，并随细胞刺激而波动。O-GlcNAc经常与蛋白质磷酸化竞争，这两种修饰在信号、转录、癌基因和肿瘤抑制因子的功能调节方面存在广泛的交叉。糖尿病是这一应用的生物驱动因素，它是一种疾病的主要例子，在这种疾病中，胰岛素抵抗水平的增加，胰岛素的抗凋亡作用的抑制，循环中O-GlcNAc的改变已知会扰乱正常的信号转导，并与脂肪细胞因子水平的诱导，糖异生的解除调控，以及胰岛素基因转录的调节有关。我们将利用一种新的免疫原策略，针对三种在糖尿病信号抑制中发挥作用的蛋白质上O-GlcNAc修饰的四个位点，开发特异性的O-GlcNAc抗体。因此，如果我们成功，这项初步研究中产生的单抗除了为这一策略提供测试系统外，还将对糖尿病研究产生直接影响。我们预测，在第一阶段结束时，我们将展示一种战略，使GlycoScience能够以已知和受控的成本生产各种O-GlcNAc位点特定的单抗。我们认为，这些将对疾病研究产生深远的影响。

DESCRIPTION (provided by applicant): O-glycosylation of serine and threonine of nuclear and cytoplasmic proteins by a single beta-N- acetyl-D-glucosamine moiety (O-GlcNAc) is a ubiquitous post-translational modification that is highly dynamic and fluctuates in response to cellular stimuli. O-GlcNAc often competes with protein phosphorylation, and these two modifications have extensive crosstalk in the regulation of signaling, transcription, and the functions of oncogenes and tumor suppressors. Diabetes, the biological driver for this application, is a prime example of a disease where increased levels of insulin resistance, inhibition of the anti-apoptotic action of insulin, alteration of circulating O-GlcNAc is known to disrupt normal signaling, and has been associated with the induction of adipocytokine levels, deregulation of gluconeogenesis, and modulation of insulin gene transcription. We will utilize a new immunogen strategy to develop site-specific O-GlcNac antibodies to four sites of O-GlcNAc modification on three proteins that play a role in signaling suppression in diabetes. Consequently, if we are successful, the mAbs generated in this initial study will have an immediate impact on diabetes research in addition to providing a test system for this strategy. We predict that at the end of phase 1, we will have demonstrated a strategy that will allow GlycoScientific to produce a wide range of O-GlcNAc site-specific MAbs, at a known and contained cost. We feel that these will have far reaching implications in disease research.