Physiological roles of ovotransferrin

• Published in: Biochimica et biophysica acta Vol. 1820; no. 3; pp. 218 - 225
• Main Authors: Giansanti, Francesco, Leboffe, Loris, Pitari, Giuseppina, Ippoliti, Rodolfo, Antonini, Giovanni
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2012
• Subjects: Animals; Anti-Bacterial Agents; antibacterial properties; Antifungal Agents; birds; Birds - immunology; Birds - physiology; blood serum; Conalbumin - blood; Conalbumin - chemistry; Conalbumin - physiology; egg albumen; Egg White - chemistry; extracellular fluids; glycoproteins; granules; Immunity, Innate; innate immunity; Ion Transport; Iron - metabolism; Iron transport; Lactoferrin; lymphocytes; mammals; Models, Molecular; Natural immunity; Ovotransferrin; peptides; Protein evolution; Protein Structure, Tertiary; sequence homology; Serum transferrin; transferrin; Serum transferrin; Protein evolution; Natural immunity; Lactoferrin; Ovotransferrin; Iron transport
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/j.bbagen.2011.08.004

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. ► Multiple physiological roles of ovotransferrin are reviewed. ► Ovotransferrin plays a major role in avian natural immunity. ► Experimental evidences support that the ovotransferrin is a multi-functional protein. ► New biotechnolgical applications of ovotransferrin could be envisaged.