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Lee Et Al. (lee + et_al)
Selected AbstractsDiscovery of HLA-B*480102 in TaiwaneseINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 1 2008M. J. Chen Summary Human leucocyte antigen (HLA)-B48, an antigen within 7C CREG (cross-reacting group) (Steiner et al., 2001) that cross-reacts frequently with HLA-B40 (i.e. HLA-B60 and -B61) group of antibodies serologically, can be found in Alaskan Natives (Leffell et al., 2002), Amerindians (Martinez-Naves et al., 1997), African Americans, Caucasians, and Oriental ethnicities (Mori et al., 1997; Schipper et al., 1997; Cao et al., 2001; Middleton et al., 2004; Hong et al., 2005; Itoh et al., 2005; Lee et al., 2005; Ogata et al., 2007). Sequencing investigations demonstrated that the common allele encoding the B48 antigen is B*4801 (Belich et al., 1992). To date, there are at least 16 WHO recognized B*48 alleles according to the most recent report from the WHO nomenclature committee (Marsh et al., 2005). Here we report a newly discovered allele B*480102, a variant of B*4801, detected in a 55-year-old Taiwanese patient of Minan origin (southern China). [source] Characterization of tissue-specific LIM domain protein (FHL1C) which is an alternatively spliced isoform of a human LIM-only protein (FHL1)JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2001Enders Kai On Ng Abstract We have cloned and characterized another alternatively spliced isoform of the human four-and-a-half LIM domain protein 1 (FHL1), designated FHL1C. FHL1C contains a single zinc finger and two tandem repeats of LIM domains at the N-terminus followed by a putative RBP-J binding region at the C-terminus. FHL1C shares the same N-terminal two-and-a-half LIM domains with FHL1 but different C-terminal protein sequences. Due to the absence of the exon 4 in FHL1C, there is a frame-shift in the 3, coding region. Sequence analysis indicated that FHL1C is the human homolog of murine KyoT2. The Northern blot and RT-PCR results revealed that FHL1 is widely expressed in human tissues, including skeletal muscle and heart at a high level, albeit as a relatively low abundance transcript in brain, placenta, lung, liver, kidney, pancreas, and testis. In contrast, FHL1C is specifically expressed in testis, skeletal muscle, and heart at a relatively low level compared with FHL1. The expression of FHL1C transcripts was also seen in aorta, left atrium, left, and right ventricles of human heart at low level. Immunoblot analysis using affinity-purified anti-FHL1C antipeptide antibodies confirmed a 20 kDa protein of FHL1C in human skeletal muscle and heart. Unlike FHL1B, which is another FHL1 isoform recently reported by our group and localized predominantly in the nucleus [Lee et al., 1999], FHL1C is localized both in the nucleus and cytoplasm of mammalian cell. J. Cell. Biochem. 82: 1,10, 2001. © 2001 Wiley-Liss, Inc. [source] Phosphatidic acid activates a wound-activated MAPK in Glycine maxTHE PLANT JOURNAL, Issue 5 2001Sumin Lee Summary Many plant species demonstrate a systemic increase in phosphatidic acid (PA) levels after being wounded (Lee et al., 1997). To understand the role of PA in wound signal transduction, we investigated if PA can activate protein kinases in soybean (Glycine max L.). We found that a MAPK is activated in soybean seedlings in both wounded and neighboring unwounded leaves. The wound-activated soybean kinase is specifically recognized by an antibody against the alfalfa MAPK, SIMK. When PA production is inhibited with n -butanol, an inhibitor of phospholipase D, the wound-induced activation of the MAPK is suppressed, suggesting that an elevation in PA levels is essential for its activation. Supporting this is the observation that exogenous PA activates the MAPK in suspension-cultured soybean cells. Activation of the 49 kDa MAPK occurs almost exclusively by PA, as other lipids are unable to or can only weakly activate the kinase. PA-induced activation of the MAPK is not a direct effect on the kinase but is mediated by upstream kinases. Our results suggest that PA acts as a second messenger in wound-induced MAPK signaling in plants. [source] Techniques and tactics used in determining the structure of the trimeric ebolavirus glycoproteinACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2009Jeffrey E. Lee The trimeric membrane-anchored ebolavirus envelope glycoprotein (GP) is responsible for viral attachment, fusion and entry. Knowledge of its structure is important both for understanding ebolavirus entry and for the development of medical interventions. Crystal structures of viral glycoproteins, especially those in their metastable prefusion oligomeric states, can be difficult to achieve given the challenges in production, purification, crystallization and diffraction that are inherent in the heavily glycosylated flexible nature of these types of proteins. The crystal structure of ebolavirus GP in its trimeric prefusion conformation in complex with a human antibody derived from a survivor of the 1995 Kikwit outbreak has now been determined [Lee et al. (2008), Nature (London), 454, 177,182]. Here, the techniques, tactics and strategies used to overcome a series of technical roadblocks in crystallization and phasing are described. Glycoproteins were produced in human embryonic kidney 293T cells, which allowed rapid screening of constructs and expression of protein in milligram quantities. Complexes of GP with an antibody fragment (Fab) promoted crystallization and a series of deglycosylation strategies, including sugar mutants, enzymatic deglycosylation, insect-cell expression and glycan anabolic pathway inhibitors, were attempted to improve the weakly diffracting glycoprotein crystals. The signal-to-noise ratio of the search model for molecular replacement was improved by determining the structure of the uncomplexed Fab. Phase combination with Fab model phases and a selenium anomalous signal, followed by NCS-averaged density modification, resulted in a clear interpretable electron-density map. Model building was assisted by the use of B -value-sharpened electron-density maps and the proper sequence register was confirmed by building alternate sequences using N-linked glycan sites as anchors and secondary-structural predictions. [source] Predicting phenotypic effects of gene perturbations in C. elegans using an integrated network modelBIOESSAYS, Issue 8 2008Karsten Borgwardt Predicting the phenotype of an organism from its genotype is a central question in genetics. Most importantly, we would like to find out if the perturbation of a single gene may be the cause of a disease. However, our current ability to predict the phenotypic effects of perturbations of individual genes is limited. Network models of genes are one tool for tackling this problem. In a recent study, (Lee et al.) it has been shown that network models covering the majority of genes of an organism can be used for accurately predicting phenotypic effects of gene perturbations in multicellular organisms. BioEssays 30:707,710, 2008. © 2008 Wiley Periodicals, Inc. [source] Structure of the T109S mutant of Escherichia coli dihydroorotase complexed with the inhibitor 5-fluoroorotate: catalytic activity is reflected by the crystal formACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2007Mihwa Lee Crystals of a single-point mutant (T109S) of Escherichia coli dihydroorotase (DHOase) with diminished activity grown in the presence of l -dihydroorotate (l -DHO) are tetragonal, with a monomer in the asymmetric unit. These crystals are extremely unstable and disintegrate shortly after formation, which is followed by the growth of orthorhombic crystals from the remnants of the tetragonal crystals or at new nucleation sites. Orthorhombic crystals, for which a structure has previously been reported [Thoden et al. (2001), Biochemistry, 40, 6989,6997; Lee et al. (2005), J. Mol. Biol.348, 523,533], contain a dimer of DHOase in the asymmetric unit; the active site of one monomer contains the substrate N -carbamyl- l -aspartate (l -CA-asp) and the active site of the other monomer contains the product of the reaction, l -DHO. In the subunit with l -DHO in the active site, a surface loop (residues 105,115) is `open'. In the other subunit, with l -CA-asp in the active site, the loop folds inwards, forming specific hydrogen bonds from the loop to the l -CA-asp. The tetragonal crystal form can be stabilized by crystallization in the presence of the inhibitor 5-fluoroorotate (FOA), a product (l -DHO) mimic. Crystals of the complex of T109S DHOase with FOA are tetragonal, space group P41212, with unit-cell parameters a = b = 72.6, c = 176.1,Å. The structure has been refined to R and Rfree values of 0.218 and 0.257, despite severe anisotropy of the diffraction. In this structure, the flexible loops are both in the `open' conformation, which is consistent with FOA, like l -DHO, binding at both sites. The behaviour of the T109S mutant crystals of DHOase in the presence of l -DHO is explained by initial binding of l -DHO to both subunits, followed by slow conversion to l -CA-asp, with consequent movement of the flexible loop and dissolution of the crystals. Orthorhombic crystals are then able to grow in the presence of l -DHO and l -CA-asp. [source] Reply on Lee et al., Tight orbit syndrome: a previously unrecognized cause of open-angle glaucomaACTA OPHTHALMOLOGICA, Issue 5 2010Sung B. Lee No abstract is available for this article. [source] | ||||||||||||||||