Giansanti Francesco, Leboffe Loris, Pitari Giuseppina, Ippoliti Rodolfo, Antonini Giovanni
Department of Biology, University of Roma TRE, viale Marconi 446, I-00146 Roma, Italy.
Biochim Biophys Acta. 2012 Mar;1820(3):218-25. doi: 10.1016/j.bbagen.2011.08.004. Epub 2011 Aug 10.
Ovotransferrin is an iron-binding glycoprotein, found in avian egg white and in avian serum, belonging to the family of transferrin iron-binding glycoproteins. All transferrins show high sequence homology. In mammals are presents two different soluble glycoproteins with different functions: i) serum transferrin that is present in plasma and committed to iron transport and iron delivery to cells and ii) lactoferrin that is present in extracellular fluids and in specific granules of polymorphonuclear lymphocytes and committed to the so-called natural immunity. To the contrary, in birds, ovotransferrin remained the only soluble glycoprotein of the transferrin family present both in plasma and egg white.
Substantial experimental evidences are summarized, illustrating the multiple physiological roles of ovotransferrin in an attempt to overcome the common belief that ovotransferrin is a protein dedicated only to iron transport and to iron withholding antibacterial activity.
Similarly to the better known family member protein lactoferrin, ovotransferrin appears to be a multi-functional protein with a major role in avian natural immunity.
Biotechnological applications of ovotransferrin and ovotransferrin-related peptides could be considered in the near future, stimulating further research on this remarkable protein. This article is part of a Special Issue entitled Transferrins: Molecular mechanisms of iron transport and disorders.
卵转铁蛋白是一种铁结合糖蛋白，存在于禽蛋清和禽血清中，属于转铁蛋白铁结合糖蛋白家族。所有转铁蛋白都具有高度的序列同源性。在哺乳动物中存在两种具有不同功能的可溶性糖蛋白：i）血清转铁蛋白，存在于血浆中，负责铁的运输和向细胞输送铁；ii）乳铁蛋白，存在于细胞外液和多形核淋巴细胞的特定颗粒中，负责所谓的天然免疫。相反，在鸟类中，卵转铁蛋白仍然是转铁蛋白家族中唯一同时存在于血浆和蛋清中的可溶性糖蛋白。
总结了大量实验证据，阐述了卵转铁蛋白的多种生理作用，试图打破卵转铁蛋白只是一种仅负责铁运输和具有铁螯合抗菌活性的蛋白质的普遍观念。
与更为人熟知的家族成员蛋白乳铁蛋白类似，卵转铁蛋白似乎是一种多功能蛋白，在禽类天然免疫中起主要作用。
在不久的将来可以考虑卵转铁蛋白及与卵转铁蛋白相关肽的生物技术应用，这将刺激对这种非凡蛋白质的进一步研究。本文是名为“转铁蛋白：铁运输和疾病的分子机制”的特刊的一部分。
