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Updated: Apr 1, 2026

Targeting Cysteine Thiols for in Vitro Site-specific Glycosylation of Recombinant Proteins
Published on: October 4, 2017
O-Fucosylation of CCN1 is required for its secretion
Yuki Niwa1, Takehiro Suzuki2, Naoshi Dohmae2
1Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Abstract:
The matricellular protein CCN1, also known as Cyr61, is a secreted ligand and has numerous functions. Human CCN1 contains one predicted O-fucosylation site in the thrombospondin type-1 repeat (TSR1) domain at Thr(242). In this report, we demonstrated that CCN1 is O-fucosylated at Thr(242) using mass spectrometry. Deficiency of O-fucosylation resulted in the decrement of the cell surface localization and the secretion of CCN1. Furthermore, knockdown of protein O-fucosyltransferase 2, which modifies a specific Ser/Thr residue in the TSR1 domain, decreased secreted levels of CCN1. These results demonstrated that O-fucosylation of CCN1 at Thr(242) regulates its secretion.
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