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Cytosolic peptide: N -glycanase (NGLY1) is an enzyme that cleaves N -glycans from glycoproteins that has been retrotranslocated from the endoplasmic reticulum (ER) lumen into the cytosol. It is known that NGLY1 is involved in the degradation of cytosolic glycans (non-lysosomal glycan degradation) as well as ER-associated degradation, a quality control system for newly synthesized glycoproteins. The discovery of NGLY1 deficiency, which is caused by mutations in the human NGLY1 gene and results in multisystemic symptoms, has attracted interest in the physiological functions of NGLY1 in mammals. Studies using various animal models led to the identification of possible factors that contribute to the pathogenesis of NGLY1 deficiency. In this review, we summarize phenotypic consequences that have been reported for various Ngly1 -deficient rodent models and discuss future perspectives to provide more insights into the physiological functions of NGLY1. [ABSTRACT FROM AUTHOR]

Cytosolic peptide: N -glycanase (PNGase; NGLY1), an enzyme responsible for de-glycosylation of N -glycans on glycoproteins, is known to play pivotal roles in a variety of biological processes. In 2012, NGLY1 deficiency, a rare genetic disorder, was reported and since then, more than 100 patients have now been identified worldwide. Patients with this disease exhibit several common symptoms that are caused by the dysfunction of NGLY1. However, correlation between the severity of patient symptoms and the extent of the reduction in NGLY1 activity in these patients remains to be clarified, mainly due to the absence of a facile quantitative assay system for this enzyme, especially in a crude extract as an enzyme source. In this study, a quantitative, non-radioisotope (RI)-based assay method for measuring recombinant NGLY1 activity was established using a BODIPY-labeled asialoglycopeptide (BODIPY-ASGP) derived from hen eggs. With this assay, the activities of 27 recombinant NGLY1 mutants that are associated with the deficiency were examined. It was found that the activities of three (R469X, R458fs and H494fs) out of the 27 recombinant mutant proteins were 30–70% of the activities of wild-type NGLY1. We further developed a method for measuring endogenous NGLY1 activity in crude extracts derived from cultured cells, patients' fibroblasts, iPS cells or peripheral blood mononuclear cells (PBMCs), using a glycosylated cyclopeptide (GCP) that exhibited resistance to the endogenous proteases in the extract. Our methods will not only provide new insights into the molecular mechanism responsible for this disease but also promises to be applicable for its diagnosis. [ABSTRACT FROM AUTHOR]

Laser-induced fluorescence excitation and dispersed fluorescence spectra of jet-cooled chlorotoluene molecules were obtained. Weak bands were seen near the origin for p- and m-chlorotoluene, and designated to be the internal rotation of the methyl group in the S0 and S1 states. The potential barrier heights for the S0 and S1 states of p-chlorotoluene were quite small, indicating that the methyl rotor is almost free in both states.

The C-glycopeptide and the natural high-mannose N-glycopeptide can be synthesized through a strategy with two main steps. The first is a chemical synthesis of a GlcNAc containing glycopeptide or neoglycopeptide, and the second is an enzymatic transfer of a Mann-GlcNAc moiety to the terminal GlcNAc residue in the peptide. This approach also allows the biological activity of these glycopeptides towards a range of glycoamidases to be assessed. It can be established that the C-glycopeptide is the first, broad spectrum inhibitor for glycoamidases.

Researchers have examined expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) at both messenger RNA (mRNA) and protein levels in order to assess the contributions of humoral and hemodynamic factors to cardiac phenotypic changes connected with chronic pressure overload. Proportions of myosin isoforms in transplanted cervical hearts that were mechanically unloaded were also investigated. It was found that the cardiac hypertrophic response was boosted by humoral factor(s) secondary to the pressure overload produced by aortic coarctation.