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1.
N-linked oligosaccharide changes with oncogenic transformation require sialylation of multiantennae 总被引:1,自引:0,他引:1
U V Santer R DeSantis K J H?rd J A van Kuik J F Vliegenthart B Won M C Glick 《European journal of biochemistry》1989,181(1):249-260
Glycopeptides derived from NIH 3T3 fibroblasts and these cells transformed by transfection with human DNA containing oncogene H-ras were analyzed by 500-MHz 1H-NMR spectroscopy and binding to immobilized lectins. The cells were metabolically labeled with D-[3H]glucosamine or L-[3H]fucose and the glycopeptides included in Bio-Gel P-10 (Mr 5000-3500) were separated into neutral and charged fractions on DEAE-cellulose. The major portion (80%) of these [3H]fucose glycopeptides from the non-transformed NIH 3T3 fibroblasts were neutral or contained one or two charged residues, whereas 90% of the glycopeptides from the transformed cells contained two or more charged residues. The structure of the predominant neutral glycopeptide from the non-transformed NIH 3T3 cells was determined by 1H-NMR spectroscopy to be tetraantennary containing terminal Gal alpha 1----3. (formula; see text) This structure was verified by binding to the immobilized alpha-Gal-specific lectin, Griffonia simplicifolia I and leukoagglutinating phytohemagglutinin from Phaseolus vulgaris (L-PHA), which binds certain tri- or tetraantennary glycopeptides. In contrast, the structure derived by NMR spectroscopy of one of the predominant charged glycopeptides from the transformed cells was triantennary containing terminal NeuNAc alpha 2----3 in addition to Gal alpha 1----3. (formula; see text) In attempting to verify this structure by lectin-binding properties it was found that removal of NeuNAc alpha 2----3 reduced the affinity to L-PHA - agarose. The other major glycopeptides of the transformed cells which were more charged also cotained NeuNAc alpha 2----3 but no NeuNAc alpha 2----6 or Gal alpha 1----3. A tentative structure was proposed for the major glycopeptide of the first charged class from NIH 3T3 cells on the basis of lectin-binding properties and the NMR spectrum which showed, in addition to NeuNAc alpha 2----3, the presence of NeuNAc alpha 2----6 and Gal alpha 1----3. On the basis of the NMR spectrum and other results, it is concluded that the presence of tetraantennary oligosaccharides are not sufficient for the transformed oligosaccharide phenotype. Rather, the tri- or tetraantennae must be sialylated in alpha 2----3 linkage, on more than one antennae, when properties of transformation are expressed in NIH 3T3 cells. Prior to transformation the tetraantennary oligosaccharides of these cells are terminated in alpha-Gal residues, whereas after transformation alpha-Gal residues appear to be replaced by NeuNAc alpha 2----3.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
2.
Evangelia G. Kranias Ramesh C. Gupta Gyorgyi Jakab Hae Won Kim Nancy A. E. Steenaart Stephen T. Rapundalo 《Molecular and cellular biochemistry》1988,82(1-2):37-44
Summary Canine cardiac sarcoplasmic reticulum is phosphorylated by adenosine 3,5-monophosphate (cAMP)-dependent and by calcium · calmodulin-dependent protein kinases on a 27 000 proteolipid, called phospholamban. Both types of phosphorylation are associated with an increase in the initial rates of Ca2+ transport by SR vesicles which reflects an increased turnover of elementary steps of the calcium ATPase reaction sequence. The stimulatory effects of the protein kinases on the calcium pump may be reversed by an endogenous protein phosphatase, which can dephosphorylate both the CAMP-dependent and the calcium · calmodulin-dependent sites on phospholamban. Thus, the calcium pump in cardiac sarcoplasmic reticulum appears to be under reversible regulation mediated by protein kinases and protein phosphatases. 相似文献
3.
Anna L. Trifillis Myong Won Kahng 《In vitro cellular & developmental biology. Plant》1990,26(5):441-446
Summary We have developed an in vitro model of human papillary collecting duct cells isolated from cadaver kidneys using methods similar
to those we previously reported for the isolation of human proximal tubule cells. To date we have isolated papillary collecting
duct cells from 100 normal human kidneys. Papillae were dissected and digested in Cellgro containing 400 U/ml collagenase.
Cells were plated on fibronectin-coated culture flasks at a density of 104 live cells/ml in Cellgro supplemented with insulin and 10% fetal bovine serum. Confluent monolayers, which were able to withstand
600 mOsm for 8 h, were obtained within 10 to 15 d. Cells of primary isolates and first passages exhibited epithelial cell ultrastructure
including cell junctions, microvilli, and cilia. A dark-brown reaction product was observed in these cells when stained by
the immunoperoxidase method with peroxidase-labeled peanut lectin (Arachis hypogaea), which binds specifically to human distal tubule and collecting duct cells. These cells were negative for Factor-VIII (a
marker for endothelial cells) and γ-glutamyltransferase (a marker for proximal tubule cells). High activities of the glycolytic
enzyme pyruvate kinase and arginine vasopressin-stimulated cAMP production in these cells are consistent with a distal nephron
origin. The results indicate that human collecting duct cells can be isolated and cultured to provide an in vitro system to
probe pathogenetic mechanisms of potential nephrotoxins.
Part of this work was presented at a Symposium of the Center for Alternatives to Animal Testing, April 4–5, 1989, Johns Hopkins
Medical Institutions, Baltimore, MD 21205.
This work was supported in part by grants R01-AI24179, PO1-A804393 for the Public Health Service, U.S. Department of Health
and Human Services, and by a grant from the National Kidney Foundation, Baltimore, MD affiliate. 相似文献
4.
Journal of Physiology and Biochemistry - The browning of white adipose tissue (WAT) has attracted considerable attention in the scientific community as a popular strategy for enhancing energy... 相似文献
5.
Haengdueng Jeong Youn Woo Lee In Ho Park Hyuna Noh Sung-Hee Kim Jiseon Kim Donghun Jeon Hui Jeong Jang Jooyeon Oh Dain On Chanyang Uhm Kyungrae Cho Heeju Oh Suhyeon Yoon Jung Seon Seo Jeong Jin Kim Sang-Hyuk Seok Yu Jin Lee Seung-Min Hong Se-Hee An Seo Yeon Kim Young Been Kim Ji-Yeon Hwang Hyo-Jung Lee Hong Bin Kim Dae Gwin Jeong Daesub Song Manki Song Man-Seong Park Kang-Seuk Choi Jun Won Park Jun-Young Seo Jun-Won Yun Jeon-Soo Shin Ho-Young Lee Ki Taek Nam Je Kyung Seong 《Disease models & mechanisms》2022,15(11)
6.
7.
Hea Jin Ryu Ji-Eun Kim Yeon-Joo Kim Ji-Yang Kim Won IL Kim So-Yeon Choi Min-Ju Kim Tae-Cheon Kang 《Cellular and molecular neurobiology》2013,33(4):575-585
Transient receptor potential canonical channel (TRPC) is a nonselective cation channel permeable to Ca2+, which express in many cell types, including neurons. However the alterations in TRPC receptor expressions in response to status epilepticus (SE) have not been explored. Therefore, the present study was designated to elucidate the roles of TRPC3 in neuronal death and vasogenic edema within the rat piriform cortex (PC) following SE. In non-SE animals, TRPC3 immunoreactivity was abundantly detected in the PC. Following SE, TRPC3 immunoreactivity was increased in neurons. Furthermore, TRPC3 expression was detected in endothelial cells that did not contain it in non-SE animals. Loss of SMI-71 (a blood–brain barrier antigen) immunoreactivity was also observed in TRPC3 positive endothelial cells. In addition, FJB positive neurons and vasogenic edema were noticeably detected in the PC. To directly determine whether TRPC3 activation is correlated to SE-induced vasogenic edema formation and neuronal damages in the PC, the effect of Pyr-3 (a TRPC3 antagonist) on SE-induced insults were investigated. Pyr-3 infusion effectively attenuated vasogenic edema in the PC as compared to the vehicle. Therefore, our findings indicate that TRPC3 activation/overexpression induced by SE may involve BBB disruption and neuronal damages in the rat PC following SE. Therefore, the present study was TRPC3 may play an important role in SE-induced vasogenic edema formation through BBB disruptions in the rat PC. 相似文献
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10.
Simulation of sequential batch reactor (SBR) operation for simultaneous removal of nitrogen and phosphorus 总被引:3,自引:0,他引:3
Ho Nam Chang Ra Kyung Moon Byung Geon Park Seong-Jin Lim Dong Won Choi Woo Gi Lee Seok Lyong Song Yong Hee Ahn 《Bioprocess and biosystems engineering》2000,23(5):513-521
Modeling of the operation of sequential batch reactor (SBR) was performed to find out optimum design parameters for simultaneous removal of nitrogen and phosphorus in a small-scale wastewater treatment plant. The models were set up with material balances on SBR operation and Monod kinetics. The model parameters were obtained to best fit the experimental results in a small scale SBR. The models were useful in optimizing hydraulic retention time (HRT) and successfully simulated operations of SBR in a larger scale. Especially the model predicted well the reactions occurring in the filling period as well as the effect of dilution, and evaluated the performance of SBR process under diverse operating conditions. 相似文献