Galectin-3 guides intracellular trafficking of some human serotransferrin glycoforms

Research output: Contribution to journalJournal articlepeer-review

  • Carl Michael Carlsson
  • Per Bengtson
  • Helena Cucak
  • Hakon Leffler
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.
Original languageEnglish
JournalThe Journal of Biological Chemistry
ISSN0021-9258
DOIs
Publication statusPublished - 7 Aug 2013

ID: 49740939