• BMB Reports
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• v.32 no.3
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• pp.215-225
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• 1999

Phytochromes (with gene family members phyA, B, C, D, and E) are a wavelength-dependent light sensor or switch for gene regulation that underscore a number of photo responsive developmental and morphogenic processes in plants. Recently, phytochrome-like pigment proteins have also been discovered in prokaryotes, possibly functioning as an auto-phosphorylating/phosphate-relaying two-component signaling system (Yeh et al., 1997). Phytochromes are photochromically convertible between the light sensing Pr and regulatory active Pfr forms. Red light converts Pr to Pfr, the latter having a "switch-on" conformation. The Pfr form triggers signal transduction pathways to the downstream responses including the expression of photosynthetic and other growth-regulating genes. The components involved in and the molecular mechanisms of the light signal transduction pathways are largely unknown, although G-proteins, protein kinases, and secondary messengers such as $Ca^{2+}$ ions and cGMP are implicated. The 124-127 kDa phytochromes form homodimeric structures. The N-terminal half contains the tetrapyrrolic phytochromobilin for red/far-red light absorption. The C-terminal half includes both a dimerization motif and regulatory box where the red light signal perceived by the chromophore-domain is recognized and transduced to initiate the signal transduction cascade. A working model for the inter-domain signal communication within the phytochrome molecule is proposed in this Review.

• 대한치주과학회:학술대회논문집
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• 2007.11a
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• pp.115-116
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• 2007

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.2017-2022
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• 2014

Novel baculovirus vector systems recombined with coding genes of polyhedron promoter, vesicular stomatitis virus G (VSVG), polyA, cytomegalovirus (CMV) promoter, enhanced green fluorescent protein (EGFP), and protein transduction domain (PTD) were constructed. These recombinant baculovirus vector systems were applied into human foreskin fibroblast cells and compared the effects of gene transfer and gene expression of these recombinant baculovirus vector systems with control vector system. From this study, it showed that these novel recombinant baculovirus vector systems were superior efficacy to control vector system in view of gene transfer and gene expression.

• IMMUNE NETWORK
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• v.9 no.3
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• pp.75-83
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• 2009

Recent years have seen an explosion of new knowledge defining the molecular events that are critical for development and activation of immune cells. Much of this new information has come from a careful molecular dissection of key signal transduction pathways that are initiated when immune cell receptors are engaged. In addition to the receptors themselves and critical effector molecules, these signaling pathways depend on adapters, proteins that have no intrinsic effector function but serve instead as scaffolds to nucleate multimolecular complexes. This review summarizes some of what has been learned about one such adapter protein, SH2 domain-containing leukocyte phosphoprotein of 76 kDa (SLP-76), and how it regulates and integrates signals after engagement of immunoreceptors and integrins on various immune cell lineages.

• Biomedical Science Letters
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• v.7 no.2
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• pp.59-64
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• 2001

Nebulin is an unusually large actin-binding protein specific to the skeletal muscle of vertebrates. The correlation of nebulin size with thin filament length have led to the suggestion that nebulin acts as a molecular ruler for the length of thin filaments. An SH3 domain occupies the C terminus of nebulin, in the sarcomeric Z-disk and is preceded by a 120-residue stretch containing multiple putative phosphorylation sites. SH3 domain mediates protein-protein interaction involved in the subcellular localization of proteins, cytoskeletal organization and signal transduction. However the binding partner and physiological role of nebulin SH3 domains remains unknown. Using the yeast two-hybrid system, we identified supervillin, an actin-binding protein, as a nebulin SH3 domain-interacting protein. The SH3 domain of nebulin binds to the sequence encoding amino acids 977 to 1335 of supervillin. But the sequence encoding amino acids 977 to 1335 displays weaker binding than the sequence encoding amino acids 977 to 1788.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.199-204
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• 2012

We evaluated the role of Tat-mediated p66shc transduction on the activation of endothelial nitric oxide synthase in cultured mouse endothelial cells. To construct the Tat-p66shc fusion protein, human full length p66shc cDNA was fused with the Tat-protein transduction domain. Transduction of TAT-p66shc showed a concentration- and time-dependent manner in endothelial cells. Tat-mediated p66shc transduction showed increased hydrogen peroxide and superoxide production, compared with Tat-p66shc (S/A), serine 36 residue mutant of p66shc. Tat-mediated p66shc transduction decreased endothelial nitric oxide synthase phosphorylation in endothelial cells. Furthermore, Tat-mediated p66shc transduction augmented TNF-${\alpha}$-induced p38 MAPK phosphorylation in endothelial cells. These results suggest that Tat-mediated p66shc transduction efficiently inhibited endothelial nitric oxide synthase phosphorylation in endothelial cells.

• Molecules and Cells
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• v.19 no.2
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• pp.191-197
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• 2005

The human immunodeficiency virus type 1 (HIV-1) Tat protein transduction domain (PTD) is responsible for highly efficient protein transduction across plasma membranes. In a previous study, we showed that Tat-Cu,Zn-superoxide dismutase (Tat-SOD) can be directly transduced into mammalian cells across the lipid membrane barrier. In this study, we fused the human SOD gene with a Tat PTD transduction vector at its N- and/or C-terminus. The fusion proteins (Tat-SOD, SOD-Tat, Tat-SOD-Tat) were purified from Escherichia coli and their ability to enter cells in vitro and in vivo compared by Western blotting and immunohistochemistry. The transduction efficiencies and biological activities of the SOD fusion protein with the Tat PTD at either terminus were equivalent and lower than the fusion protein with the Tat PTD at both termini. The availability of a more efficient SOD fusion protein provides a powerful vehicle for therapy in human diseases related to this anti-oxidant enzyme and to reactive oxygen species.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.21-21
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• 1999

A signal of Fas-mediated apoptosis is transferred through an adaptor protein FADD by interactions between death domains of Fas and FADD. To understand the signal transduction mechanism of Fas-mediated apoptosis, we solved the solution structure of a murine FADD death domain.(omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.43-43
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• 1997

Platelet production in blood is regulated by a lineage specific humoral factor called thrombopoietin (TPO). The amino terminal domain of TPO (TPO-N) has a sequence homology to erythropoietin (EPO) and is responsible for the signal transduction mediated by the TPO receptor, c-mpl.(omitted)

• BMB Reports
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• v.32 no.2
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• pp.196-202
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• 1999

The existence of the Ras-independent signal transduction pathway of insulin leading to DNA synthesis was investigated in Rat-1 fibroblasts overexpressing human insulin receptor (HIRc-B) using the single-cell microinjection technique. Microinjection of a dominant-negative mutant $Ras^{N17}$ protein into quiescent HIRc-B cells inhibited the DNA synthesis stimulated by insulin. Microinjection of oncogenic H-$Ras^{V12}$ protein ($H-Ras^{V12}$) (0.1 mg/ml) induced DNA synthesis by 35%, whereas that of control-injected IgG was induced by 20%. When the marginal amount of oncogenic H-$Ras^{V12}$ protein was coinjected with a dominant-negative mutant of the H-Ras protein ($Ras^{N17}$), DNA synthesis was 35% and 74% in the absence and presence of insulin, respectively. This full recovery of DNA synthesis by insulin suggests the existence of the Ras-independent pathway. The same recovery was observed in the cells coinjected with either H-$Ras^{V12}$ plus H-$Ras^{N17}$ plus SH2 domain of the p85 subunit of PI3-kinase ($p85^{SH2-N}$) or H-$Ras^{V12}$ plus H-$Ras^{N17}$ plus interfering anti-Shc antibody. When co-injected with a dominant-negative H-$Ras^{N17}$, the DNA synthesis induced by the Ras-independent pathway was blocked. These results indicate that the Ras-independent pathway of insulin leading to DNA synthesis exists, bypassing the p85 of PI3-kinase and Shc protein, and requires Rac1 protein.