Docytosis*Received for publication, August 23, 2013, and in revised type, January 15, 2014 Published, JBC Papers in Press, February 5, 2014, DOI 10.1074/jbc.M113.Henrik J. J gensen? Kristina Johansson, Daniel H. Madsen? Astrid Porse, Maria C. Melander, Kristine R. S ensen, Christoffer Nielsen, Thomas H. Bugge? Niels Behrendt, and Lars H. Engelholm1 In the Finsen Laboratory, Rigshospitalet/Biotech Study and Innovation Center (BRIC), DK-2200 Copenhagen, Denmark and ?Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, MarylandBackground: Mannose receptor family members are candidate mediators of intracellular collagen degradation. Outcomes: In spite of frequent candidate collagen-binding domains and endocytic capacity throughout the family, only uPARAP/Endo180 and MR internalize collagens. Conclusion: A multi-domain interplay inside the active receptors governs collagen endocytosis. Significance: Identification from the principal collagen receptors enables elucidation with the biological importance of intracellular collagen degradation. Members with the well-conserved mannose receptor (MR) protein loved ones have already been functionally implicated in diverse biological and pathological processes. Importantly, a proposed widespread function is definitely the internalization of collagen for intracellular degradation occurring throughout bone improvement, cancer invasion, and fibrosis protection. This functional partnership is recommended by a prevalent endocytic capability and a candidate collagen-binding domain. Here we performed a comparative investigation of every single member’s capability to facilitate intracellular collagen degradation. As expected, the members of the family uPARAP/Endo180 and MR bound collagens within a purified program and internalized collagens for degradation in cellular settings.N-Fmoc-2,5-difluoro-L-phenylalanine Chemical name In contrast, the remaining members of the family, PLA2R and DEC-205, showed no collagen binding activity and were unable to mediate collagen internalization. To pinpoint the structural elements discriminating collagen from non-collagen receptors, we constructed a series of receptor chimeras and loss- and gain-of-function mutants. Working with this approach we identified a essential collagen binding loop inside the suggested collagen binding area (an FN-II domain) in uPARAP/Endo180 and MR, which was distinct in PLA2R or DEC-205. Nonetheless, we also identified that an active FN-II domain was not a enough determinant to permit collagen internalization by way of these receptors.Price of 2,6-Bis(aminomethyl)pyridine Nevertheless, this ability could be acquired by the transfer of a larger segment of uPARAP/Endo180 (the Cysrich domain, the FN-II domain and two CTLDs) to DEC-205.PMID:23912708 These data underscore the importance with the FN-II domain in uPARAP/Endo180 and MR-mediated collagen internalization but at the exact same time uncover a critical interplay with flanking domains.* This work was supported by the NIDCR Intramural Analysis System (D. M.and T. H. B.), the Danish Cancer Society, the Danish Medical Study Council, the Danish Cancer Investigation Foundation, the Novo Nordisk Foundation, the Danish National Analysis Foundation (Danish-Chinese Center for Proteases and Cancer) and also the European Community’s Seventh Framework Programme FP7/2007-2011 below Grant agreement n?01279 (to M. C. M. and N. B.), by the Lundbeck Foundation (to D. H. M. and L. H. E.), the “Grosserer Alfred Nielsen og Hustrus” foundation (to L. H. E.). The function was also supported by private grants from Rigshospitalet/Copenhagen University Hos.