Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat, Solan, Himachal Pradesh, India.
PLoS One. 2013 Jul 24;8(7):e69916. doi: 10.1371/journal.pone.0069916. Print 2013.
The increasing number of patients suffering from urolithiasis represents one of the major challenges which nephrologists face worldwide today. For enhancing therapeutic outcomes of this disease, the pathogenic basis for the formation of renal stones is the need of hour. Proteins are found as major component in human renal stone matrix and are considered to have a potential role in crystal-membrane interaction, crystal growth and stone formation but their role in urolithiasis still remains obscure.
Proteins were isolated from the matrix of human CaOx containing kidney stones. Proteins having MW>3 kDa were subjected to anion exchange chromatography followed by molecular-sieve chromatography. The effect of these purified proteins was tested against CaOx nucleation and growth and on oxalate injured Madin-Darby Canine Kidney (MDCK) renal epithelial cells for their activity. Proteins were identified by Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF MS) followed by database search with MASCOT server. In silico molecular interaction studies with CaOx crystals were also investigated.
Five proteins were identified from the matrix of calcium oxalate kidney stones by MALDI-TOF MS followed by database search with MASCOT server with the competence to control the stone formation process. Out of which two proteins were promoters, two were inhibitors and one protein had a dual activity of both inhibition and promotion towards CaOx nucleation and growth. Further molecular modelling calculations revealed the mode of interaction of these proteins with CaOx at the molecular level.
We identified and characterized Ethanolamine-phosphate cytidylyltransferase, Ras GTPase-activating-like protein, UDP-glucose:glycoprotein glucosyltransferase 2, RIMS-binding protein 3A, Macrophage-capping protein as novel proteins from the matrix of human calcium oxalate stone which play a critical role in kidney stone formation. Thus, these proteins having potential to modulate calcium oxalate crystallization will throw light on understanding and controlling urolithiasis in humans.
越来越多的尿路结石患者是当今全球肾病学家面临的主要挑战之一。为了提高这种疾病的治疗效果，肾结石形成的病理基础是当务之急。蛋白质是人类肾石基质的主要成分，被认为在晶体-膜相互作用、晶体生长和结石形成中具有潜在作用，但它们在尿石症中的作用仍不清楚。
从人草酸钙结石基质中分离出蛋白质。MW>3 kDa 的蛋白质进行阴离子交换层析，然后进行分子筛层析。测试这些纯化蛋白对草酸钙成核和生长的影响，以及对草酸损伤的 Madin-Darby Canine Kidney (MDCK) 肾上皮细胞的活性。用基质辅助激光解吸/电离飞行时间（MALDI-TOF MS）鉴定蛋白质，然后用 MASCOT 服务器的数据库搜索进行鉴定。还研究了与 CaOx 晶体的计算机分子相互作用研究。
通过 MALDI-TOF MS 从草酸钙肾结石基质中鉴定出 5 种蛋白质，然后用 MASCOT 服务器的数据库搜索进行鉴定，这些蛋白质具有控制结石形成过程的能力。其中两种蛋白质是促进剂，两种是抑制剂，一种蛋白质对 CaOx 成核和生长具有促进和抑制双重活性。进一步的分子建模计算揭示了这些蛋白质与 CaOx 在分子水平上的相互作用模式。
我们从人草酸钙结石基质中鉴定并表征了乙醇胺磷酸胞苷转移酶、Ras GTP 酶激活样蛋白、UDP-葡萄糖：糖蛋白葡萄糖基转移酶 2、RIMS 结合蛋白 3A、巨球蛋白-帽蛋白，这些蛋白质在肾结石形成中起着关键作用。因此，这些具有调节草酸钙结晶潜力的蛋白质将有助于理解和控制人类尿石症。
