Copper-dependent autocleavage of glypican-1 heparan sulfate by nitric oxide derived from intrinsic nitrosothiols.
نویسندگان
چکیده
Cell surface heparan sulfate proteoglycans facilitate uptake of growth-promoting polyamines (Belting, M., Borsig, L., Fuster, M. M., Brown, J. R., Persson, L., Fransson, L.-A., and Esko, J. D. (2002) Proc. Natl. Acad. Sci. U. S. A. 99, 371-376). Increased polyamine uptake correlates with an increased number of positively charged N-unsubstituted glucosamine units in the otherwise polyanionic heparan sulfate chains of glypican-1. During intracellular recycling of glypican-1, there is an NO-dependent deaminative cleavage of heparan sulfate at these glucosamine units, which would eliminate the positive charges (Ding, K., Sandgren, S., Mani, K., Belting, M., and Fransson, L.-A. (2001) J. Biol. Chem. 276, 46779-46791). Here, using both biochemical and microscopic techniques, we have identified and isolated S-nitrosylated forms of glypican-1 as well as slightly charged glypican-1 glycoforms containing heparan sulfate chains rich in N-unsubstituted glucosamines. These glycoforms were converted to highly charged species upon treatment of cells with 1 mm l-ascorbate, which releases NO from nitrosothiols, resulting in deaminative cleavage of heparan sulfate at the N-unsubstituted glucosamines. S-Nitrosylation and subsequent deaminative cleavage were abrogated by inhibition of a Cu(2+)/Cu(+) redox cycle. Under cell-free conditions, purified S-nitrosylated glypican-1 was able to autocleave its heparan sulfate chains when NO release was triggered by l-ascorbate. The heparan sulfate fragments generated in cells during this autocatalytic process contained terminal anhydromannose residues. We conclude that the core protein of glypican-1 can slowly accumulate NO as nitrosothiols, whereas Cu(2+) is reduced to Cu(+). Subsequent release of NO results in efficient deaminative cleavage of the heparan sulfate chains attached to the same core protein, whereas Cu(+) is oxidized to Cu(2+).
منابع مشابه
Copper-dependent co-internalization of the prion protein and glypican-1.
Heparan sulfate chains have been found to be associated with amyloid deposits in a number of diseases including transmissible spongiform encephalopathies. Diverse lines of evidence have linked proteoglycans and their glycosaminoglycan chains, and especially heparan sulfate, to the metabolism of the prion protein isoforms. Glypicans are a family of glycosylphosphatidylinositol-anchored, heparan ...
متن کاملindírectly via hypoxia-inducible factor, nitric oxide synthase and the heparan sulfate proteoglycan glypican-1, which is deglycanated in a vitamin C- and copper-dependent reaction. In fibroblasts from patients with Niemann-Pick C disease, heparan sulfate
متن کامل
The amyloid precursor protein (APP) of Alzheimer disease and its paralog, APLP2, modulate the Cu/Zn-Nitric Oxide-catalyzed degradation of glypican-1 heparan sulfate in vivo.
Processing of the recycling proteoglycan glypican-1 involves the release of its heparan sulfate chains by copper ion- and nitric oxide-catalyzed ascorbate-triggered autodegradation. The Alzheimer disease amyloid precursor protein (APP) and its paralogue, the amyloid precursor-like protein 2 (APLP2), contain copper ion-, zinc ion-, and heparan sulfate-binding domains. We have investigated the po...
متن کاملThe heparan sulfate-specific epitope 10E4 is NO-sensitive and partly inaccessible in glypican-1.
The monoclonal antibody 10E4, which recognizes an epitope supposed to contain N-unsubstituted glucosamine, is commonly used to trace heparan sulfate proteoglycans. It has not been fully clarified if the N-unsubstituted glucosamine is required for antibody recognition and if all heparan sulfates carry this epitope. Here we show that the epitope can contain N-unsubstituted glucosamine and that ni...
متن کاملDefective nitric oxide-dependent, deaminative cleavage of glypican-1 heparan sulfate in Niemann-Pick C1 fibroblasts.
Exit of recycling cholesterol from late endosomes is defective in Niemann-Pick C1 (NPC1) and Niemann-Pick C2 (NPC2) diseases. The traffic route of the recycling proteoglycan glypican-1 (Gpc-1) may also involve late endosomes and could thus be affected in these diseases. During recycling through intracellular compartments, the heparan sulfate (HS) side chains of Gpc-1 are deaminatively degraded ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 277 36 شماره
صفحات -
تاریخ انتشار 2002