PHOSPHOLIPID HEAD GROUP RECOGNITION IN MEMBRANE BINDING PROTEIN ANNEXIN V

一种用于检测和鉴定的质谱方法 血浆蛋白转甲状腺素蛋白（TTR）的变体 开发 在TTR中发现的单个氨基酸取代是 与家族性甲状腺素运载蛋白淀粉样变性（ATTR）密切相关， 遗传性退化性疾病 ATTR的明确诊断 依赖于TTR变体的检测和鉴定。 的 这里开发的方法是基于使用 免疫沉淀。 变异体的检测是通过大量 电喷雾质谱法测定完整蛋白质 （ESIN 4S）。 液相色谱/电喷雾质谱 蛋白质胰蛋白酶消化物的光谱法（LC/ESIMS）分析 随后进行基质辅助激光解吸电离 飞行时间质谱（NLkLDI-TOFMS）和NLALDI后源 相关回收色谱馏分的衰减（PSDMS） 含有变异肽的蛋白质允许鉴定未知的 变体。 用ATTR的血清成功地验证了该方法 已知变异（Va 130 - 4 Met和Va 1122-->Ile）的患者。 新TTR 使用上述方法检测并鉴定了变体Ser 23->Asn 等电聚焦和限制性内切酶分析 未能确定该变体的性质。

A mass spectrometry approach for the detection and identification of variants of theplasma protein transthyretin (TTR) is being developed. The single amino acid substitutions found in TTR are closely associated with familial transthyretin amyloidosis (ATTR), a hereditary degenerative disease. A definitive diagnosis of ATTR relies on the detection and identification of TTRvariants. The approach being developed here is based on isolation of serum TTR using immunoprecipitation. The detection of the variant is achieved by mass measurement of the intact protein with electrospray mass spectrometry (ESIN4S). The liquid chromatography/electrospray ionization mass spectrometry (LC/ESIMS) analysis of the tryptic digest of the protein followed by subsequent matrix-assisted laser desorption ionization time-of-flight mass spectrometry (NLkLDI-TOFMS) and NLALDI post source decay (PSDMS) of the relevant recovered chromatographic fraction containing the variant peptide allow the identification of unknown variants. The method wassuccessfully tested using serum from ATTR patients with known variants (Va130-4Met and Va1122-->Ile). A new TTR variant, Ser23->Asn, was detected and identified using the above method where isoelectric focusing and restriction enzyme analysis failed to identify the nature of thevariant.