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31.
Cleavage of the matricellular protein SPARC by matrix metalloproteinase 3 produces polypeptides that influence angiogenesis 总被引:8,自引:0,他引:8
Sage EH Reed M Funk SE Truong T Steadele M Puolakkainen P Maurice DH Bassuk JA 《The Journal of biological chemistry》2003,278(39):37849-37857
SPARC, a matricellular protein that affects cellular adhesion and proliferation, is produced in remodeling tissue and in pathologies involving fibrosis and angiogenesis. In this study we have asked whether peptides generated from cleavage of SPARC in the extracellular milieu can regulate angiogenesis. Matrix metalloproteinase (MMP)-3, but not MMP-1 or 9, showed significant activity toward SPARC. Limited digestion of recombinant human (rhu)SPARC with purified catalytic domain of rhuMMP-3 produced three major fragments, which were sequenced after purification by HPLC. Three synthetic peptides (Z-1, Z-2, and Z-3) representing motifs from each fragment were tested in distinct assays of angiogenesis. Peptide Z-1 (3.9 kDa, containing a Cu2+-binding sequence KHGK) exhibited a biphasic effect on [3H]thymidine incorporation by cultured endothelial cells and stimulated vascular growth in the chick chorioallantoic membrane (CAM). In contrast, peptides Z-2 (6.1 kDa, containing Ca2+-binding EF hand-1) and Z-3 (2.2 kDa, containing neither Cu2+-binding motifs nor EF hands), inhibited cell proliferation in a concentration-dependent manner and exhibited no effects on vessel growth in the CAM. Reciprocal results were obtained in a migration assay in native collagen gels: peptide Z-1 was ineffective over a range of concentrations, whereas Z-2 or Z-3 stimulated cell migration. Therefore, proteolysis of SPARC by MMP-3 produced peptides that regulate endothelial cell proliferation and/or migration in vitro in a mutually exclusive manner. One of these peptides containing KHGK also demonstrated a concentration-dependent effect on angiogenesis. 相似文献
32.
报道了越南荨麻科(Urticaceae)冷水花属(Pilea Lindl.)一新记录种——基心叶冷水花(P.basicordata W.T.Wang ex C.J.Chen)。该种在越南Pu Hu自然保护区发现,与产自越南北部的P.balansae Gagnep.相似,主要区别在于其雄花序聚伞圆锥状,托叶大,叶先端渐尖或短尾状渐尖。 相似文献
33.
Phan Tu Quy Nguyen Khoa Hien Nguyen Chi Bao Doan Thanh Nhan Dang Van Khanh Nguyen Thi Ai Nhung Truong Quy Tung Nguyen Dinh Luyen Duong Tuan Quang 《Luminescence》2015,30(3):325-329
A new rhodamine–ethylenediamine–nitrothiourea conjugate (RT) was synthesized and its sensing property as a fluorescent chemodosimeter toward metal ions was explored in water media. Analytical results from absorption and fluorescence spectra revealed that the addition of Hg2+ ions to the aqueous solution of the chemodosimeter RT caused a distinct fluorescence OFF–ON response with a remarkable visual color change from colorless to pink; however, no clear spectral and color changes were observed from other metal ions including: Zn2+, Cu2+, Cd2+, Pb2+, Ag+, Fe2+, Cr3+, Co3+, Ni2+, Ca2+, Mg2+, K+ and Na+. The sensing results and the molecular structure suggested that a Hg2+‐induced a desulfurization reaction and cyclic guanylation of the thiourea moiety followed by ring‐opening of the rhodamine spirolactam in RT are responsible for a distinct fluorescence turn‐on signal, indicating that RT is a remarkably sensitive and selective chemodosimeter for Hg2+ ions in aqueous solution. Hg2+ within a concentration range from 0.1 to 25 μM can be determined using RT as a chemodosimeter and a detection limit of 0.04 μM is achieved. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
34.
Ralf Buettner Le Xuan Truong Nguyen Bijender Kumar Corey Morales Chao Liu Lisa S. Chen Tea Pemovska Timothy W. Synold Joycelynne Palmer Ryan Thompson Ling Li Dinh Hoa Hoang Bin Zhang Lucy Ghoda Claudia Kowolik Mika Kontro Calum Leitch Krister Wennerberg Xiaochun Yu Ching-Cheng Chen David Horne Varsha Gandhi Vinod Pullarkat Guido Marcucci Steven T. Rosen 《Journal of cellular physiology》2019,234(9):16295-16303
35.
Lee Seokjin Trịnh Cao Sơn Lee Won Je Jeong Chan Young Truong Hai An Chung Namhyun Kang Chon-Sik Lee Hojoung 《Journal of plant research》2020,133(2):231-244
Journal of Plant Research - Plant growth promoting rhizobacteria (PGPR) are a group of bacteria that promote plants growth in the rhizosphere. PGPRs are involved in various mechanisms that... 相似文献
36.
Gihoon Cha Shiva Mohajernia Nhat Truong Nguyen Anca Mazare Nikita Denisov Imgon Hwang Patrik Schmuki 《Liver Transplantation》2020,10(6)
Recently, sodium ion batteries (SIBs) have been widely investigated as one of the most promising candidates for replacing lithium ion batteries (LIBs). For SIBs or LIBs, designing a stable and uniform solid electrolyte interphase (SEI) at the electrode–electrolyte interface is the key factor to provide high capacity, long‐term cycling, and high‐rate performance. In this paper, it is described how a remarkably enhanced SEI layer can be obtained on TiO2 nanotube (TiO2 NTs) arrays that allows for a strongly improved performance of sodium battery systems. Key is that a Li+ pre‐insertion in TiO2 NTs can condition the SEI for Na+ replacement. SIBs constructed with Li‐pre‐inserted NTs deliver an exceptional Na+ cycling stability (e.g., 99.9 ± 0.1% capacity retention during 250 cycles at a current rate of 50 mA g?1) and an excellent rate capability (e.g., 132 mA h g?1 at a current rate of 1 A g?1). The key factor in this outstanding performance is that Li‐pre‐insertion into TiO2 NTs leads not only to an enhanced electronic conductivity in the tubes, but also expands the anatase lattice for facilitated subsequent Na+ cycling. 相似文献
37.
Paul M. Sanders Anhthu Q. Bui Koen Weterings K. N. McIntire Yung-Chao Hsu Pei Yun Lee Mai Thy Truong T. P. Beals R. B. Goldberg 《Sexual plant reproduction》1999,11(6):297-322
We identified Arabidopsis thaliana sterility mutants by screening T-DNA and EMS-mutagenized lines and characterized several male-sterile mutants with defects
specific for different anther processes. Approximately 44 and 855 sterile mutants were uncovered from the T-DNA and EMS screens,
respectively. Several mutants were studied in detail with defects that included the establishment of anther morphology, microspore
production, pollen differentiation, and anther dehiscence. Both non-dehiscencing and late-dehiscencing mutants were identified.
In addition, pollenless mutants were observed with either apparent meiotic defects and/or abnormalities in cell layers surrounding
the locules. Two mutant alleles were identified for the POLLENLESS3 locus which have defects in functional microspore production that lead to the degeneration of cells within the anther locules.
pollenless3–1 contains a T-DNA insertion that co-segregates with the mutant phenotype and pollenless3–2 has a large deletion in the POLLENLESS3 gene. The POLLENLESS3 gene has no known counterparts in the GenBank, but encodes a protein containing putative nuclear localization and protein-protein
interaction motifs. The POLLENLESS3 gene was shown recently to be the same as MS5, a previously described Arabidopsis
thaliana male-sterility mutant. Three genes were identified in the POLLENLESS3 genomic region: GENEY, POLLENLESS3, and β9-TUBULIN. The segment of the Arabidopsis
thaliana genome containing the POLLENLESS3 and β9-TUBULIN genes is duplicated and present on a different chromosome. Analysis of the POLLENLESS3 expression pattern determined that the 1.3-kb POLLENLESS3 mRNA is localized specifically within meiotic cells in the anther
locules and that POLLENLESS3 mRNA is present only during late meiosis.
Received: 15 October 1998 / Revision accepted: 19 November 1998 相似文献
38.
Binh-Nguyen Truong Koei Okazaki Hideyuki Suzuki Hitoshi Neda Toshimitsu Fukiharu Xuan-Tham Le Akira Suzuki 《Mycoscience》2006,47(2):84-90
This study was carried out to elucidate the poorly understood processes of arthroconidiation through coremium formation using
Pleurotus cystidiosus subsp. abalonus. The coremia exclusively produced dikaryotic arthroconidia with the remnant of a clamp connection. Cells in the subapical
zone of the hyphal bundle reduced their length by division before arthroconidiation. Approximately 400 000 arthroconidia were
produced by a coremium in 1 day, with constant productivity over a 2-week period. Continuous cell extension and division in
the coremium stipe supplied cells for arthroconidiation at the coremium apex, which is surrounded by a liquid droplet (coremioliquid).
Maintenance of moisture with coremioliquid was necessary for arthroconidiation. The coremioliquid formation was performed
by active liquid transportation in the hyphae, a process that was blocked by the microtubule depolymerization agent thiabendazole. 相似文献
39.
The understanding of sex determination in general, but in particular in mammals, has been a subject of scientific speculation for a long time. It has been shown that in many vertebrate and invertebrate species, the sex of an individual is determined by the individual's chromosomal constitution. Initial studies of classical genetic searching for sex-transforming mutations and the scrupulous analyses of modified phenotypes have shed light on the mechanism(s) of sex-determination. They paved the road to successful studies at molecular level. After a brief review on sex determination in chosen model species, the “Drosophila system” is presented to exemplify a possible general principle for sex determinism. 相似文献
40.
QUASIMODO1 encodes a putative membrane-bound glycosyltransferase required for normal pectin synthesis and cell adhesion in Arabidopsis 下载免费PDF全文
Bouton S Leboeuf E Mouille G Leydecker MT Talbotec J Granier F Lahaye M Höfte H Truong HN 《The Plant cell》2002,14(10):2577-2590
Pectins are a highly complex family of cell wall polysaccharides. As a result of a lack of specific mutants, it has been difficult to study the biosynthesis of pectins and their role in vivo. We have isolated two allelic mutants, named quasimodo1 (qua1-1 and qua1-2), that are dwarfed and show reduced cell adhesion. Mutant cell walls showed a 25% reduction in galacturonic acid levels compared with the wild type, indicating reduced pectin content, whereas neutral sugars remained unchanged. Immersion immunofluorescence with the JIM5 and JIM7 monoclonal antibodies that recognize homogalacturonan epitopes revealed less labeling of mutant roots compared with the wild type. Both mutants carry a T-DNA insertion in a gene (QUA1) that encodes a putative membrane-bound glycosyltransferase of family 8. We present evidence for the possible involvement of a glycosyltransferase of this family in the synthesis of pectic polysaccharides, suggesting that other members of this large multigene family in Arabidopsis also may be important for pectin biosynthesis. The mutant phenotype is consistent with a central role for pectins in cell adhesion. 相似文献