Fbs1 protects the malfolded glycoproteins from the attack of peptide:N-glycanase

Journal Article · Fri Oct 26 04:00:00 EDT 2007 · Biochemical and Biophysical Research Communications

DOI:https://doi.org/10.1016/j.bbrc.2007.08.056· OSTI ID:21032942

Yamaguchi, Yoshiki ^[1]; Hirao, Takeshi ^[1]; Sakata, Eri ^[1]; Kamiya, Yukiko ^[1]; Kurimoto, Eiji ^[1]; Yoshida, Yukiko ^[2]; Suzuki, Tadashi ^[3]; Tanaka, Keiji ^[2]; Kato, Koichi ^[1]

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1. Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603 (Japan)
2. Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613 (Japan)
3. Core Research for Evolutional Science and Technology (CREST), Japan Science Technology Agency, Saitama 332-0012 (Japan)

Fbs1 is a cytosolic lectin putatively operating as a chaperone as well as a substrate-recognition subunit of the SCF{sup Fbs1} ubiquitin ligase complex. To provide structural and functional basis of preferential binding of Fbs1 to unfolded glycoproteins, we herein characterize the interaction of Fbs1 with a heptapeptide carrying Man{sub 3}GlcNAc{sub 2} by nuclear magnetic resonance (NMR) spectroscopy and other biochemical methods. Inspection of the NMR data obtained by use of the isotopically labeled glycopeptide indicated that Fbs1 interacts with sugar-peptide junctions, which are shielded in native glycoprotein, in many cases, but become accessible to Fbs1 in unfolded glycoproteins. Furthermore, Fbs1 was shown to inhibit deglycosylation of denatured ribonuclease B by a cytosolic peptide:N-glycanase (PNGase). On the basis of these data, we suggest that Fbs1 captures malfolded glycoproteins, protecting them from the attack of PNGase, during the chaperoning or ubiquitinating operation in the cytosol.

• OSTI ID: 21032942
• Journal Information: Biochemical and Biophysical Research Communications, Journal Name: Biochemical and Biophysical Research Communications Journal Issue: 3 Vol. 362; ISSN 0006-291X; ISSN BBRCA9
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
BASIC INTERACTIONS
GLYCOPROTEINS
LIGASES
NUCLEAR MAGNETIC RESONANCE
PEPTIDES
RNA-ASE
SACCHAROSE
SPECTROSCOPY
SUBSTRATES