Daisuke Takakura

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Many glycoproteins and glycosaminoglycans are approved for clinical use. Carbohydrate moieties in biopharmaceuticals affect not only their physicochemical properties and thermal stability, but also their reactivity with their receptors and circulating half-life. Modification of glycans is one target of drug design for enhancement of efficacy. Meanwhile,(More)
β-Galactoside α2,6-sialyltranferase 1 (ST6GAL1) catalyzes the addition of terminal α2,6-sialylation to N-glycans. Increased expression of ST6GAL1 has been reported in diverse carcinomas and highly correlates with tumor progression. Here, we report that St6gal1 transcription and α2,6-sialylated N-glycans are up-regulated during TGF-β-induced(More)
Recently, we established two mouse monoclonal antibodies (R-10G and R-17F). The R-17F antibody (IgG1 subtype) exhibited a strong cytotoxic effect on hiPS/ES cells. The R-17F antigen isolated from a total lipid extract of hiPS (Tic) cells was identified as LNFP I (Fucα1–2Galβ1–3GlcNAcβ1–3Galβ1–4Glc). In the present study, R-17F binding proteins were isolated(More)
During translation, stop codon read-through occasionally happens when the stop codon is misread, skipped, or mutated, resulting in the production of aberrant proteins with C-terminal extension. These extended proteins are potentially deleterious, but their regulation is poorly understood. Here we show in vitro and in vivo evidence that mouse cFLIP-L with a(More)
We analyzed the structure of the N-linked oligosaccharides enzymatically liberated from the organic matrix (OM) component in the nacreous layer of Japanese pearl oyster: Pinctada fucata. The lectin-blot analysis of the soluble OM after separation by SDS-PAGE, four components, with sizes of approximately 55 kDa, 35 kDa, 25 kDa, and 21 kDa were detected with(More)
Recently, the Golgi phosphoprotein 3 (GOLPH3) and its yeast homolog Vps74p have been characterized as essential for the Golgi localization of glycosyltransferase in yeast. GOLPH3 has been identified as a new oncogene that is commonly amplified in human cancers to modulate mammalian target of rapamycin signaling. However, the molecular mechanisms of the(More)
In response to the successful use of monoclonal antibodies (mAbs) in the treatment of various diseases, systems for expressing recombinant mAbs using transgenic animals or plants have been widely developed. The silkworm (Bombyx mori) is a highly domesticated insect that has recently been used for the production of recombinant proteins. Because of their(More)
RATIONALE Glycan heterogeneity on recombinant human erythropoietin (rEPO) product is considered to be one of the critical quality attributes, and similarity tests of glycan heterogeneities are required in the manufacturing process changes and developments of biosimilars. A method for differentiating highly complex and diverse glycosylations is needed to(More)
In-gel digestion followed by LC/MS/MS is widely used for the identification of trace amounts of proteins and for the site-specific glycosylation analysis of glycoproteins in cells and tissues. A major limitation of this technique is the difficulty in acquiring reliable mass spectra for peptides present in minute quantities and glycopeptides with high(More)
The cytoplasmic peptide:N-glycanase (Ngly1 in mammals) is a de-N-glycosylating enzyme that is highly conserved among eukaryotes. It was recently reported that subjects harboring mutations in the NGLY1 gene exhibited severe systemic symptoms (NGLY1-deficiency). While the enzyme obviously has a critical role in mammals, its precise function remains unclear.(More)