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Chen SH, Habib G, Yang CY, Gu ZW, Lee BR, Weng SA, Silberman SR, Cai SJ, Deslypere JP, Rosseneu M. Apolipoprotein B-48 is the product of a messenger RNA with an organ-specific in-frame stop codon. Science 1987; 238:363-6. [PMID: 3659919 DOI: 10.1126/science.3659919] [Citation(s) in RCA: 550] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The primary structure of human apolipoprotein (apo) B-48 has been deduced and shown by a combination of DNA excess hybridization, sequencing of tryptic peptides, cloned complementary DNAs, and intestinal messenger RNAs (mRNAs) to be the product of an intestinal mRNA with an in-frame UAA stop codon resulting from a C to U change in the codon CAA encoding Gln2153 in apoB-100 mRNA. The carboxyl-terminal Ile2152 of apoB-48 purified from chylous ascites fluid has apparently been cleaved from the initial translation product, leaving Met2151 as the new carboxyl-terminus. These data indicate that approximately 85% of the intestinal mRNAs terminate within approximately 0.1 to 1.0 kilobase downstream from the stop codon. The other approximately 15% have lengths similar to hepatic apoB-100 mRNA even though they have the same in-frame stop codon. The organ-specific introduction of a stop codon to a mRNA appears unprecedented and might have implications for cryptic polyadenylation signal recognition and RNA processing.
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327
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Byrnes L, Luo CC, Li WH, Yang CY, Chan L. Chicken apolipoprotein A-I: cDNA sequence, tissue expression and evolution. Biochem Biophys Res Commun 1987; 148:485-92. [PMID: 3118875 DOI: 10.1016/0006-291x(87)91137-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Using an antibody against chicken apolipoprotein (apo) A-I, we identified multiple cDNA clones for the protein in two intestinal cDNA libraries in lambda gt11. The complete nucleotide sequence of chicken apoA-I cDNA was determined. The sequence predicts a mature protein of 240 amino acids, a 6-amino acid propeptide and an 18-amino acid signal peptide. Using a 32P-cDNA probe, we detected the presence of apoA-I mRNA in 21 day old chicken intestine, liver, kidney, spleen, breast muscle and brain. The primary sequence of apoA-I contains numerous tandem repeats of 11 and 22 residues in a manner similar to the mammalian proteins. Our analysis of apoA-I sequences from human, rabbit, dog, rat, and chicken indicates that the rate of amino acid substitution is considerably faster in the rat lineage than in other mammalian lineages.
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328
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Lan HJ, Ye SD, Cai JJ, Yang CY, Sun ZQ, Liang H. Re-replacement of mitral valve--a report of 10 cases. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1987; 7:157-60. [PMID: 3448241 DOI: 10.1007/bf02888210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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329
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Lewis CG, Fields M, Craft N, Yang CY, Reiser S. Alteration of pancreatic enzyme activities in small intestine of rats fed a high fructose, low copper diet. J Nutr 1987; 117:1447-52. [PMID: 2442328 DOI: 10.1093/jn/117.8.1447] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This study describes the progressive effects on pancreatic enzyme activities from washings of the small intestine of rats fed diets containing either 62% starch (S) or fructose (F), with 0.6 mg copper/kg diet (-Cu) or 6.0 mg copper/kg diet (+Cu) from 21 to 61 d of age. Hepatic copper concentration of the copper-deficient groups was 50% of that of the copper-supplemented groups. Body and relative pancreatic weights were lower in the F-Cu dietary group than in any other group. Relative liver weight was significantly higher in the fructose dietary groups than in the starch dietary groups. There were significant carbohydrate (CHO) X week and Cu X week interactions for luminal amylase activities and the CHO X Cu X week interaction was significant for luminal lipase and trypsin activities. The lowest enzyme activities were observed in the F-Cu-fed rats. The CHO X week interaction was significant for chymotrypsin with the lowest enzyme activities in the fructose-fed rats. It appears that high dietary fructose and low dietary copper interact to produce greatly reduced pancreatic enzyme activities in small intestinal washings. We speculate that subsequent digestive and absorptive abnormalities during a period of rapid growth may account for the severe morbidity and mortality in copper-deficient, fructose-fed rats.
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330
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Chen PQ, Yang CY, Liu TK. Surgical reconstruction as a palliative treatment for metastatic malignancies of the spine. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1987; 86:855-63. [PMID: 2445900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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331
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Yang CY, Paesler MA, Sayers DE. Determination of bond strengths of arsenic and arsenic chalcogen compounds using the temperature dependence of extended x-ray-absorption fine structure. PHYSICAL REVIEW. B, CONDENSED MATTER 1987; 36:980-988. [PMID: 9942903 DOI: 10.1103/physrevb.36.980] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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332
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Chiu LC, Jiang YH, Shen WW, Yang CY, Yang QH. Kinesic press--finger compress method for TMJ treatment. Cranio 1987; 5:260-8. [PMID: 3476213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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333
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Kuo YC, Chang-Chien CS, Lin DY, Sheen IS, Yang CY, Wu CS. The ultrasonic appearance of hepatic hemangioma. CHANGGENG YI XUE ZA ZHI 1987; 10:100-5. [PMID: 3331958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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334
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Chu CM, Liaw YF, Yang CY, Sheen IS. Diagnosis of acute type B hepatitis by a solid phase u-antibody capture radioimmunoassay for IgM class antibody to hepatitis B core antigen: a diagnostic proposal based on a prospective study. LIVER 1987; 7:182-7. [PMID: 3613887 DOI: 10.1111/j.1600-0676.1987.tb00340.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The diagnostic and prognostic significance of IgM anti-HBc, studied by a solid phase u-antibody capture radioimmunoassay at a serum dilution of 1:4000, was prospectively evaluated in 73 adult patients with acute hepatitis seropositive for hepatitis B surface antigen (HBsAg). Of the 73 cases, 20 (27.4%) cleared their HBsAg within 6 months, while the remaining 53 (72.6%) did not. HBsAg seroconversion to its antibody occurred in 15 (93.8%) of the 16 patients positive for IgM anti-HBc with S/N ratios above 5.0, as did 5 (26.3%) of the 19 with S/N ratios between 2.1 to 5.0, and none (0%) of the 38 negative for IgM anti-HBc (S/N ratios less than 2.1). Therefore, a S/N ratio of IgM anti-HBc above 5.0 is diagnostic for acute type B hepatitis. However, low S/N ratios (2.1-5.0) of IgM anti-HBc were observed in the early stage of some patients with acute type B hepatitis, and would increase to a level greater than 5.0 when assayed again 1-2 weeks later. It was therefore suggested that repeated testing of anti-HBc IgM is mandatory for accurate diagnosis of acute type B hepatitis in patients whose initial serum specimens showed low S/N ratios of IgM anti-HBc. According to this criterion, only 22 (30.1%) of the 73 patients with acute hepatitis seropositive for HBsAg in Taiwan were true acute type B hepatitis, of whom 2 (9.1%) subsequently became chronic HBsAg carriers, while the remaining 51 (69.9%) were chronic HBsAg carriers with other superimposed forms of acute hepatic injury.
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335
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Lan SJ, Yen YY, Yang CH, Yang CY, Chen ER. [A study on the birth weight of transplacental Yu-Cheng babies]. GAOXIONG YI XUE KE XUE ZA ZHI = THE KAOHSIUNG JOURNAL OF MEDICAL SCIENCES 1987; 3:273-82. [PMID: 3132560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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336
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Yang CY, Manoogian D, Pao Q, Lee FS, Knapp RD, Gotto AM, Pownall HJ. Lecithin:cholesterol acyltransferase. Functional regions and a structural model of the enzyme. J Biol Chem 1987; 262:3086-91. [PMID: 2880847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The amino acid sequence of human lecithin:cholesterol acyltransferase has been determined by degradation and alignment of peptides obtained from tryptic and staphylococcal digestions and the cleavage with cyanogen bromide and consisted of 416 amino acid residues. All of the tryptic peptides of lecithin:cholesterol acyltransferase were isolated and sequenced. Peptides resulting from digestion by staphylococcal protease, cyanogen bromide cleavage, or the combination of the two methods were employed to find overlapping segments. The N terminus of human lecithin:cholesterol acyltransferase was determined to be phenylalanine by sequencing the whole protein up to 40 residues while the C terminus was identified as glutamic acid through carboxypeptidase Y cleavage. Cys50 and Cys74 and Cys313 and Cys356 were identified as the two disulfide bridges while the free sulfhydryl groups were located at positions 31 and 184. The N-glycosylated sites of the protein were assigned to asparagines at positions 20, 84, 272, and 384. The active site of lecithin:cholesterol acyltransferase was identified as serine on position 181 according to its homology with other serine-type esterases which have a common structure of glycine-variable amino acid-active serine-variable amino acid-glycine (Gly-X-Ser-X-Gly) with the variable amino acids disrupting the homology. No long internal repeats or homologies with apolipoproteins were found. The secondary structure is consistent with the results of predictive algorithms. A simple model of the enzyme is proposed on the basis of available chemical data and predictive methods.
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337
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Reiser S, Powell AS, Yang CY, Canary JJ. An insulinogenic effect of oral fructose in humans during postprandial hyperglycemia. Am J Clin Nutr 1987; 45:580-7. [PMID: 3548311 DOI: 10.1093/ajcn/45.3.580] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
This study proposed to determine whether the stimulation of insulin secretion observed in humans infused with fructose when glucose levels were elevated could be observed when fructose was consumed during postprandial hyperglycemia. At 2-wk intervals, healthy volunteers consumed drinks containing glucose, starch, glucose followed 20 min later by fructose, starch followed 20 min later by fructose, and water followed 20 min later by fructose. Fructose consumption following glucose or starch drinks produced significantly higher levels of plasma insulin, but not plasma glucose, as compared to corresponding drinks consumed without fructose. Ten subjects whose blood glucose response levels were above 155 mg% after a glucose-containing drink appeared to be particularly responsive to the effects of fructose with increases in insulin levels of 60-288%. Results indicate that oral fructose can be insulinogenic in humans when blood glucose levels are elevated.
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338
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Yang CY, Meagher A, Huynh BH, Sayers DE, Theil EC. Iron(III) clusters bound to horse spleen apoferritin: an X-ray absorption and Mössbauer spectroscopy study that shows that iron nuclei can form on the protein. Biochemistry 1987; 26:497-503. [PMID: 3828319 DOI: 10.1021/bi00376a023] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Ferritin is a complex of a hollow, spherical protein and a hydrous, ferric oxide core of less than or equal to 4500 iron atoms inside the apoprotein coat; the apoprotein has multiple (ca. 12) binding sites for monoatomic metal ions, e.g., Fe(II), V(IV), Tb(III), that may be important in the initiation of iron core formation. In an earlier study we observed that the oxidation of Fe(II) vacated some, but not all, of the metal-binding sites, suggesting migration of some Fe during oxidation, possibly to form nucleation clusters; some Fe(III) remained bound to the protein. Preliminary extended X-ray absorbance fine structure (EXAFS) analysis of the same Fe(III)-apoferritin complex showed an environment distinct from ferritin cores, but the data did not allow a test of the Fe cluster hypothesis. In this paper, with improved EXAFS data and with Mössbauer data on the same complex formed with 57Fe, we clearly show that the Fe(III) in the distinctive environment is polynuclear (Fe atoms with Fe-Fe = 3.5 A and TB = 7 K). Moreover, the arrangement of atoms is such that Fe(III) atoms appear to have both carboxylate-like ligands, presumably from apoferritin, and oxo bridges to the other iron atoms. Thus the protein provides sites not only for initiation but also for nucleation of the iron core. Sites commodious enough and with sufficient conserved carboxylate ligands to accommodate such a nucleus occur inside the protein coat at the subunit dimer interfaces. Such Fe(III)-apoferritin nucleation complexes can be used to study the properties of the several members of the apoferritin family.
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339
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Dayal H, Polissar L, Yang CY, Dahlberg S. Race, socioeconomic status, and other prognostic factors for survival from colo-rectal cancer. JOURNAL OF CHRONIC DISEASES 1987; 40:857-64. [PMID: 3597687 DOI: 10.1016/0021-9681(87)90185-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Survival data on colo-rectal cancer patients from eleven comprehensive cancer centers were analyzed to examine the effect of race, socioeconomic status and other factors on the probability of survival. Complete data on variables of interest were available for 3617 colon cancer patients (2545 Caucasians and 1072 Blacks) and 1528 rectal cancer patients (1179 Caucasians and 349 Blacks). No significant difference was observed between the races with respect to either the follow-up time or the censoring pattern. For each site, Caucasian patients had a lower risk of death at any time point compared to Black patients, and this difference was maintained within categories of disease stage, sex, age and SES. The race effect was statistically significant in all multivariate models. Moreover, only race was significant in models that considered both race and SES. For either cancer, the racial difference in survival was most prominent for localized disease.
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340
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Yang YH, Yang CY, Huang JD. Mesenteric clearance of 5-fluorouracil in anesthetized rats. J Pharm Sci 1987; 76:86-7. [PMID: 3585731 DOI: 10.1002/jps.2600760121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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341
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Yang CY, Gonnerman WA, Taylor L, Nimberg RB, Polgar PR. Synthetic human parathyroid hormone fragment stimulates prostaglandin E2 synthesis by chick calvariae. Endocrinology 1987; 120:63-70. [PMID: 3465531 DOI: 10.1210/endo-120-1-63] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Synthetic human PTH N-terminal 1-34 peptide [hPTH-(1-34)] stimulates prostaglandin (PG) production by chick calvariae in culture. PGE2 was the predominant PG found by both RIA and HPLC. Stimulation of PGE2 synthesis was significant at 50 ng/ml (1.2 X 10(-8) M) hPTH-(1-34) and was dose dependent at concentrations up to 0.6 microgram/ml (1.4 X 10(-7) M). Continuous exposure of calvariae to hPTH-(1-34) showed that PGE2 production increased significantly by 1 h, reached a maximum at 24 h, and then persisted over 96 h. Indomethacin at concentrations above 5 X 10(-7) M inhibited PGE2 synthesis by both control and hPTH-(1-34)-treated bones. PTH-(1-34) stimulated bone cells to convert arachidonic acid to PGE2, but did not activate the bone to release stored arachidonate. In summary, our results show that hPTH-(1-34) stimulates PGE2 synthesis by chick calvariae. This endogenous PGE2 may be involved in bone remodeling.
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342
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Yang CY, Bryan AM, Theil EC, Sayers DE, Bowen LH. Structural variations in soluble iron complexes of models for ferritin: an x-ray absorption and Mössbauer spectroscopy comparison of horse spleen ferritin to Blutal (iron-chondroitin sulfate) and Imferon (iron-dextran). J Inorg Biochem 1986; 28:393-405. [PMID: 3102689 DOI: 10.1016/0162-0134(86)80025-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Variations in the turnover of storage iron have been attributed to differences in apoferritin and in the cytoplasm but rarely to differences in the structure of the iron core (except size). To explore the idea that the iron environment in soluble iron complexes could vary, we compared horse spleen ferritin to pharmaceutically important model complexes of hydrous ferric oxide formed from FeCl3 and dextran (Imferon) or chondroitin sulfate (Blutal), using x-ray absorption (EXAFS) and Mössbauer spectroscopy. The results show that the iron in the chondroitin sulfate complex was more ordered than in either horse spleen ferritin or the dextran complex (EXAFS), with two magnetic environments (Mössbauer), one (80%-85%) like Fe2O3 X nH2O (ferritinlike) and one (15%-20%) like Fe2O3 (hematite); since sulfate promotes the formation of inorganic hematite, the sulfate in the chondroitin sulfate most likely nucleated Fe2O3 and hydroxyl/carboxyls, which are ligands common to chondroitin sulfate, ferritin and dextran most likely nucleated Fe2O3 X nH2O. Differences in the structure of the iron complexed with chondroitin sulfate or dextran coincide with altered rates of iron release in vivo and in vitro and provide the first example relating function to local iron structure. Differences might also occur among ferritins in vivo, depending on the apoferritin (variations in anion-binding sites) or the cytoplasm (anion concentration).
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343
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Yang CY, Lee FS, Chan L, Sparrow DA, Sparrow JT, Gotto AM. Determination of the molecular mass of apolipoprotein B-100. A chemical approach. Biochem J 1986; 239:777-80. [PMID: 3827828 PMCID: PMC1147355 DOI: 10.1042/bj2390777] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Apolipoprotein B-100 (apo B-100) is the protein ligand in low-density lipoproteins that binds to a specific cell-surface receptor. Its molecular mass has been a subject of controversy. We have determined the molecular mass of the protein by a chemical approach. After complete CNBr cleavage, the C-terminal fragment of apo B-100 was purified by reverse-phase h.p.l.c. Amino acid N- and C-terminal analyses confirm that this peptide represents the C-terminal peptide as deduced from the DNA sequence of a human apo B-100 cDNA clone. A chemically synthesized peptide was used to determine the recovery of the peptide (74.72%). On the basis of these data, the molecular mass of apo B-100 was determined to be 496.82 +/- 24.84 kDa.
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344
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Yang CY, Chen SH, Gianturco SH, Bradley WA, Sparrow JT, Tanimura M, Li WH, Sparrow DA, DeLoof H, Rosseneu M. Sequence, structure, receptor-binding domains and internal repeats of human apolipoprotein B-100. Nature 1986; 323:738-42. [PMID: 3095664 DOI: 10.1038/323738a0] [Citation(s) in RCA: 368] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Apolipoprotein (apo) B-100, the major protein component in low density lipoprotein (LDL), is the ligand that binds to the LDL receptor. It is important in the metabolism of LDL and elevated plasma levels of LDL-apo B are strongly associated with increased risk of coronary artery disease. Although apo B-100 is of great clinical and biological importance its primary structure has defied chemical elucidation, mainly because of its enormous size, insolubility, and tendency to aggregate. Less than 5% of the apo B-100 sequence has been reported, despite the efforts of many laboratories over the past twenty years. Here we report the complete amino acid sequence of human apo B-100 as deducted by sequence analysis of complementary DNA clones; 2,366 of the 4,536 residues were also confirmed by direct sequencing of apo B-100 tryptic peptides. The distribution of trypsin-accessible and -inaccessible peptides of the protein on LDL is non-random and they can be grouped into 5 hypothetical domains. Of 20 potential N-glycosylation sites identified in the sequence, 13 were found by direct peptide sequencing to be glycosylated, and 4 unglycosylated. Examination of the primary structure of apo B-100 reveals that it contains a large number of long (greater than 70 residues) internal repeats and an even larger number of shorter ones, suggesting that the apo B-100 sequence was derived largely from internal duplications. Finally, using synthetic peptides of a specific region of apo B-100, we have identified a potential LDL receptor-binding domain (residues 3,345-3,381) which can bind to the LDL receptor and suppress 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase activities in cultured human fibroblasts.
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345
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Yang CY, Yang T, Pownall HJ, Gotto AM. The primary structure of apolipoprotein A-I from rabbit high-density lipoprotein. EUROPEAN JOURNAL OF BIOCHEMISTRY 1986; 160:427-31. [PMID: 3095115 DOI: 10.1111/j.1432-1033.1986.tb09990.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The amino acid sequence of rabbit apolipoprotein A-I (apo A-I) has been determined by degradation and alignment of two overlapping sets of peptides obtained from tryptic and staphylococcal digestions. All of the peptides of rabbit apo A-I resulting from digestion by staphylococcal protease were isolated and sequenced except residues 33-37. A digestion with trypsin was employed to find overlapping and missing peptides. The N-terminus of rabbit apo A-I was confirmed by sequencing the intact protein up to 20 residues while the C-terminus was identified through its homology with human apo A-I. The protein contains 241 residues in its single chain. Its primary structure is highly homologous to the reported canine apo A-I (80%) and human apo A-I (78%), but exhibits less similarity with rat apo A-I (60%). Like human apo A-I, rabbit apo A-I contains very little histidine (2) and methionine (1); it does however have two residues of isoleucine. Based on a comparison of the hydrophobic-hydrophilic character of apo A-I residues with that of the two synthetic peptides that activated lecithin: cholesterol acyltransferase (Pownall et al. and Yokoyama et al.), we found that the five segments with the highest corresponding homologies on the protein are located within the N-terminal half. This suggests that the N-terminal half of apo A-I contains the major portion of regions activating lecithin: cholesterol acyltransferase.
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346
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Chen SH, Yang CY, Chen PF, Setzer D, Tanimura M, Li WH, Gotto AM, Chan L. The complete cDNA and amino acid sequence of human apolipoprotein B-100. J Biol Chem 1986; 261:12918-21. [PMID: 3759943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We have determined the complete sequence of apolipoprotein (apo) B-100 cDNA. It is 14.1 kilobases in length and codes for a 4563-amino acid protein, including a 27-amino acid signal peptide and a 4536-amino acid mature protein. Further, we identified 2366 residues of apoB-100 by direct sequence analysis of apoB-100 tryptic peptides. The mature peptide is characterized by high hydrophobicity (0.916 kcal/residue) and predicted beta-sheet content (21%). Dot matrix analysis revealed the presence of many long internal repeats in apoB-100. The mature peptide contains 25 cysteine residues, 12 of which are in the N-terminal 500 residues. Twenty potential N-linked glycosylation sites were identified, of which 13 were proven to be glycosylated, and 4 were found not to be glycosylated by direct analysis of tryptic peptides. Our findings on apoB structure provide a basis for future experimentation on the role of apoB-100-containing lipoproteins in atherosclerosis.
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347
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Chen SH, Yang CY, Chen PF, Setzer D, Tanimura M, Li WH, Gotto AM, Chan L. The complete cDNA and amino acid sequence of human apolipoprotein B-100. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(18)69248-8] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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348
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Uhlinger DJ, Yang CY, Reed LJ. Phosphorylation-dephosphorylation of pyruvate dehydrogenase from bakers' yeast. Biochemistry 1986; 25:5673-7. [PMID: 3535883 DOI: 10.1021/bi00367a049] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The pyruvate dehydrogenase complex was purified to homogeneity from bakers' yeast (Saccharomyces cerevisiae). No pyruvate dehydrogenase kinase activity was detected at any stage of the purification. However, the purified pyruvate dehydrogenase complex was phosphorylated and inactivated with purified pyruvate dehydrogenase kinase from bovine kidney. The protein-bound radioactivity was localized in the pyruvate dehydrogenase alpha subunit. The phosphorylated, inactive pyruvate dehydrogenase complex was dephosphorylated and reactivated with purified pyruvate dehydrogenase phosphatase from bovine heart. Tryptic digestion of the 32P-labeled complex yielded a single phosphopeptide, which was purified to homogeneity. The sequence of the phosphopeptide was established to be Tyr-Gly-Gly-His-Ser(P)-Met-Ser-Asp-Pro-Gly-Thr-Thr-Tyr-Arg. This sequence is very similar to the sequence of a tryptic phosphotetradecapeptide derived from the alpha subunit of bovine kidney and heart pyruvate dehydrogenase: Tyr-His-Gly-His-Ser(P)-Met-Ser-Asp-Pro-Gly-Val-Ser-Tyr-Arg.
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349
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Liaw YF, Yang CY, Chu CM, Huang MJ. Appearance and persistence of hepatitis A IgM antibody in acute clinical hepatitis A observed in an outbreak. Infection 1986; 14:156-8. [PMID: 3759243 DOI: 10.1007/bf01645253] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
143 patients with acute hepatitis A observed during a common source outbreak were tested for IgM class antibody to hepatitis A virus (IgM anti-HAV) by commercially available solid phase radioimmunoassays. All patients were IgM anti-HAV positive though six of them were initially negative when tested within three days after the onset of symptoms. The levels of IgM anti-HAV peaked two to four weeks after onset, and declined gradually thereafter. The probability of IgM anti-HAV positivity was 25% at the end of the sixth month, and 3.4% at the end of the ninth month after onset. No significant sex or age difference in the persistence of IgM anti-HAV was observed. It was suggested that the timing of the assay and the level of IgM anti-HAV should be considered in the etiological diagnosis of acute hepatitis.
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350
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Yang CY, Ho ST, Lin C, Chang CL. [Interaction of d-tubocurarine and pancuronium on neuromuscular transmission in man]. MA ZUI XUE ZA ZHI = ANAESTHESIOLOGICA SINICA 1986; 24:105-10. [PMID: 3023782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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