Publications by authors named "Daphne Kan"

It has been reported that the neuronal intermediate filament (IF) α-internexin may plays a role in the formation of the neuronal cytoskeleton during mammalian development. From a phylogenetic viewpoint, zebrafish express inaa and inab as homologs of mammalian α-internexin. However, the distribution patterns of the inaa and inab proteins throughout zebrafish development have not been well-characterized.

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α-Internexin is a member of the neuronal intermediate filament (nIF) protein family, which also includes peripherin and neurofilament (NF) triplet proteins. Previous studies found that expression of α-internexin precedes that of the NF triplet proteins in mammals and suggested that α-internexin plays a key role in the neuronal cytoskeleton network during development. In this study, we aimed to analyze the expression patterns and function of internexin neuronal intermediate filament protein-alpha a (inaa), the encoding gene of which is a homolog of the mammalian α-internexin, during retinal development in zebrafish.

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Background: Glioblastoma is a common and aggressive type of primary brain tumor. Several anticancer drugs affect GBM (glioblastoma multiforme) cells on cell growth and morphology. Taxol is one of the widely used antineoplastic drugs against many types of solid tumors, such as breast, ovarian, and prostate cancers.

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Background: Sphere formation, one method for identifying self-renewal ability, has been used to report that cancer stem-like cells exist in rat C6 glioma cells. Recent studies suggested that cancer stem-like cells share the stem cell properties of self-renewal and multipotent ability of neural stem cells and might be regulated by microRNAs (miRNAs). However, the mechanism of miRNA involvement in the sphere formation and neural differentiation abilities of cancer stem-like cells is poorly understood.

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Intermediate filament (IF) overproduction induces abnormal accumulation of neuronal IF, which is a pathological indicator of some neurodegenerative disorders. In our study, α-Internexin- and peripherin-overexpressing PC12 cells (pINT-EGFP and pEGFP-peripherin) were used as models to study neuropathological pathways responsible for neurodegenerative diseases. Microarray data revealed that Cdk5-related genes were downregulated and Cdk5 regulatory subunit-associated protein 3 (GSK-3α and GSK-3β) were upregulated in pINT-EGFP cells.

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Background: Abnormal accumulation of neuronal intermediate filament (IF) is a pathological indicator of some neurodegenerative disorders. However, the underlying neuropathological mechanisms of neuronal IF accumulation remain unclear. A stable clone established from PC12 cells overexpressing a GFP-Peripherin fusion protein (pEGFP-Peripherin) was constructed for determining the pathway involved in neurodegeneration by biochemical, cell biology, and electronic microscopy approaches.

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A 3C-like protease (3CLpro) from the severe acute respiratory syndrome-coronavirus (SARS-CoV) is required for viral replication, cleaving the replicase polyproteins at 11 sites with the conserved Gln [downward arrow](Ser, Ala, Gly) sequences. In this study, we developed a mutant 3CLpro (T25G) with an expanded S1' space that demonstrates 43.5-fold better k(cat)/K(m) compared with wild-type in cleaving substrates with a larger Met at P1' and is suitable for tag removal from recombinant fusion proteins.

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We present here how two amino acid residues in the first helix distal from the main dimer interface modulate the dimerization and activity of a geranylgeranyl diphosphate synthase (GGPPs). The enzyme catalyzes condensation of farnesyl diphosphate and isopentenyl diphosphate to generate a C(20) product as a precursor for chlorophylls, carotenoids, and geranylgeranylated proteins. The 3D structure of GGPPs from Saccharomyces cerevisiae reveals an unique positioning of the N-terminal helix A, which protrudes into the other subunit and stabilizes dimerization, although it is far from the main dimer interface.

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