Galectin-3 guides intracellular trafficking of some human serotransferrin glycoforms

Summary, in English

Transferrin internalization via clathrin-mediated endocytosis and subsequent recycling after iron delivery has been extensively studied. Here we demonstrate a previously unrecognized parameter regulating this recycling -the binding of galectin-3 to particular glycoforms of transferrin. Two fractions of transferrin, separated by affinity chromatography based on their binding or not to galectin-3, are targeted to kinetically different endocytic pathways in HFL-1 cells expressing galectin-3 but not in SKBR3 cells lacking galectin-3; the SKBR3 cells, however can acquire the ability to target these transferrin glycoforms differently after preloading with exogenously added galectin-3. In all, this study provides the first evidence of a functional role for transferrin glycans, in intracellular trafficking after uptake. Moreover, the galectin-3 bound glycoform increased in cancer, suggesting a pathophysiological regulation. These are novel aspects of transferrin cell biology, which has previously considered only degree of iron loading, but not other forms of heterogeneity.

• Författare: Michael Carlsson; Per Bengtson; Helena Cucak; Hakon Leffler
• Avdelning/ar: Avdelningen för mikrobiologi, immunologi och glykobiologi - MIG; Avdelningen för klinisk kemi och farmakologi
• Publiceringsår: 2013
• Språk: Engelska
• Sidor: 28398-28408
• Publikation/Tidskrift/Serie: Journal of Biological Chemistry
• Volym: 288
• Issue: 39
• Länkar: http://www.jbc.org/content/early/2013/08/07/jbc.M113.487793.abstract; http://dx.doi.org/10.1074/jbc.M113.487793
• Dokumenttyp: Artikel i tidskrift
• Förlag: American Society for Biochemistry and Molecular Biology
• Ämne: Medical Biotechnology
• Nyckelord: Galectin; transferrin; glycoforms; trafficking; endocytosis
• Status: Published
• ISBN/ISSN/Övrigt: ISSN: 1083-351X