3701
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Chen Z, Lu L, Shirley M, Lee WR, Chang SH. Site-directed mutagenesis of glycine-14 and two "critical" cysteinyl residues in Drosophila alcohol dehydrogenase. Biochemistry 1990; 29:1112-8. [PMID: 2108721 DOI: 10.1021/bi00457a003] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Three amino acid residues (glycine-14, cysteine-135, and cysteine-218) previously speculated to be important for the structure and function of Drosophila melanogaster alcohol dehydrogenase have been investigated by using site-directed mutagenesis followed by kinetic analysis and chemical modification. Mutating glycine-14 to valine (G14V) virtually inactivates Drosophila ADH, and substitution of alanine at this position (G14A) causes a 31% decrease in activity. Thermal denaturation and kinetic and inhibition studies further demonstrate that replacing glycine-14 with either alanine or valine leads to structural changes in the NAD binding domain. These results provide direct evidence for the role played by glycine-14 in maintaining the correct conformation in the NAD binding domain. On the other hand, changing of cysteine-135, -218, or both to alanine (C135A, C218A, and C135A/C218A) causes no decrease in the catalytic activity of the enzyme, indicating that neither of the cysteinyl residues is essential for catalysis. C135A and wild-type enzyme are both inactivated by DTNB. In contrast, C218A and C135A/C218A are unaffected by DTNB treatment. DTNB modification of cysteine-218 can be prevented by the substrates NAD and 2-propanol, suggesting that cysteine-218 may be in the vicinity of the active site. Cysteine-135 which is normally insensitive to DTNB becomes accessible in the presence of 2-propanol and/or NAD, suggesting a conformational change induced by binding of these substrates.
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3702
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Berger R, Chen SJ, Chen Z. Philadelphia-positive acute leukemia. Cytogenetic and molecular aspects. CANCER GENETICS AND CYTOGENETICS 1990; 44:143-52. [PMID: 2404570 DOI: 10.1016/0165-4608(90)90041-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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3703
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Ma X, Lu R, Song J, Chen Z. [Effects of concentration and ratio of N, P and K on seedlings of Panax quinquefolium L]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:78-81, 125. [PMID: 2390175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Results of the orthogonal experiment of N, P and K are as follows: (1) The highest growth rate occurs in treatment 4 (N100ppm, P25ppm, K250ppm) and other features are also good. So this treatment can be used in hydroponics of seedling of P. quinquefolium. (2) The influences of N, P and K concentration on the contents of ginsenosides in different parts of seedling are different. The content of ginsenosides in aerial part is 14.72-16.72%, higher than 3.24-4.00% in root.
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3704
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Chen Z. [The status of negative charge of the RBC and glomeruli and its relation to proteinuria in adriamycin nephrosis in rats]. ZHONGHUA YI XUE ZA ZHI 1990; 70:91-3, 8. [PMID: 2161275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The status of negative charge on RBC and glomeruli and its relation to proteinuria of adriamycin nephrosis in rats were studied by electron computerized picture analysis. The results showed that the negative charge (NC) on glomeruli decreased significantly at 48 hrs and 14 days after ADR injection although there was no proteinuria simultaneously. There was a positive relation between the changes of NC on glomeruli and those on RBC (r = 0.77, p less than 0.01), and there was negative relation between either of them and proteinuria respectively (r = -0.5140, p less than 0.05; r = -0.5231, p less than 0.01). The focal fusions of foot processes occurred prior to the onset of proteinuria.
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3705
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Kimmelstiel C, Goldberg R, Decker R, Chen Z, Osganian V, Drady P, Gore J, Alpert J. Impact of female gender on incidence and prognosis of infarction-associated heart failure: The worcester heart attack trial. J Am Coll Cardiol 1990. [DOI: 10.1016/0735-1097(90)92387-h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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3706
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Tao R, Chen Z, Sheng P. First-principles Fourier approach for the calculation of the effective dielectric constant of periodic composites. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 41:2417-2420. [PMID: 9993979 DOI: 10.1103/physrevb.41.2417] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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3707
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Chen Z, Lin CD. Systematics of autoionization widths of doubly excited states of atoms. PHYSICAL REVIEW. A, GENERAL PHYSICS 1989; 40:6712-6715. [PMID: 9902069 DOI: 10.1103/physreva.40.6712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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3708
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Macintyre E, d'Auriol L, Amesland F, Loiseau P, Chen Z, Boumsell L, Galibert F, Sigaux F. Analysis of junctional diversity in the preferential V delta 1-J delta 1 rearrangement of fresh T-acute lymphoblastic leukemia cells by in vitro gene amplification and direct sequencing. Blood 1989; 74:2053-61. [PMID: 2529925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
To define the junctional diversity of T-cell antigen receptor delta gene rearrangements in fresh T-acute lymphoblastic cells and to correlate cell phenotype with the coding potential of rearrangements, we determined the junctional nucleotide sequences of 13 T-cell antigen receptor delta gene rearrangements involving the preferentially rearranged V (V delta 1) and J (J delta 1) segments using in vitro gene amplification and direct sequencing. We showed that, as in gamma delta+ cell lines, extensive junctional diversity exists in these clones and that this diversity is due both to random nucleotide deletions/additions and to the use of at least two D delta segments. We also showed that a high percentage of these rearrangements are potentially translatable (7:13) and that such functional rearrangements occur in both surface CD3+ and CD3- cells. Comparison of alpha beta versus gamma delta surface expression demonstrates that all CD3+ T acute lymphoblastic leukemias with a functional V delta 1-J delta 1 rearrangement express a surface gamma delta receptor and are recognized by the anti-delta monoclonal antibody delta TCS1, whereas a control CD3+ gamma delta+ leukemic case that had not undergone V delta 1 rearrangement was delta TCS1-. In addition, expression of this monoclonal antibody is not restricted by V gamma or C gamma usage or by the covalent or noncovalent link between gamma and delta chains.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Southern
- Gene Amplification
- Gene Rearrangement, T-Lymphocyte
- Genes
- Humans
- Leukemia-Lymphoma, Adult T-Cell/genetics
- Molecular Sequence Data
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell, gamma-delta
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3709
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Chen SJ, Chen Z, Font MP, d'Auriol L, Larsen CJ, Berger R. Structural alterations of the BCR and ABL genes in Ph1 positive acute leukemias with rearrangements in the BCR gene first intron: further evidence implicating Alu sequences in the chromosome translocation. Nucleic Acids Res 1989; 17:7631-42. [PMID: 2678002 PMCID: PMC334872 DOI: 10.1093/nar/17.19.7631] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In the Philadelphia positive bcr negative acute leukemias (Ph1+bcr- AL), the chromosomal breakpoints on chromosome 22 have been shown clustered within 10.8kb (bcr2) and 5kb (bcr3) fragments of the first intron of the BCR gene. We previously reported that the breakpoints were localized in Alu repeats on chromosomes 9 and 22 in a Ph1+bcr- acute lymphoblastic leukemia with a rearrangement involving bcr2. Molecular data of two other Ph1 translocations, one a Ph1+bcr- acute myeloblastic leukemia in the bcr2 region, and the other an acute lymphoblastic leukemia in the bcr3 region are presented. In the former, the breakpoints on chromosomes 9 and 22 are localized in Alu repeats, in regions with two inverted Alu sequences, as in our previously reported case. In the second leukemia, the breakpoints are not located in Alu sequences, but such repeats are found in their vicinity. The implications of these findings are discussed.
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3710
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Chen Z, Johnson WR, Spruch L. Atomic screening effects on electron-neutrino angular correlation and beta -decay asymmetry in allowed transitions. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1989; 40:1376-1383. [PMID: 9966111 DOI: 10.1103/physrevc.40.1376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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3711
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Wang ZG, Zhu Y, Wang SH, Pu LP, Du YH, Zhang H, Yuan C, Chen Z, Wei ML, Pu LQ. Recognition and management of Budd-Chiari syndrome: report of one hundred cases. J Vasc Surg 1989; 10:149-56. [PMID: 2760994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Budd-Chiari syndrome is an unusual form of portal hypertension caused by occlusion of the hepatic venous outflow, and it is often confused with portal hypertension caused by liver cirrhosis. Its prognosis is poor, and optimal therapy remains to be established. This is a report of 100 confirmed cases of this syndrome treated from December 1982 to March 1988 at two vascular centers in China. Sixty-two male and 38 female patients, 15 to 62 years of age (mean age, 32.6 years) were treated. Seventy-six patients had intractable ascites, 56 had esophageal varices, and 22 had upper gastrointestinal bleeding. There were 37 cases of membranous obstruction, 57 cases of occlusion of the inferior vena cava above the confluence of the hepatic veins, and 6 cases of occlusion of the hepatic veins. Eighty-one patients were operated on. Operative mortality rate was 8.6% (7/81). Follow-up from 2 to 66 months revealed that 58 of the patients operated on (72%) had good results, whereas 11 of 19 (58%) patients treated nonoperatively died within 2 months after admission. On the basis of these data we conclude that the operative procedure must be tailored to the cause and underlying pathologic characteristics. Mesoatrial shunting is the operation of choice for patients with occlusion of the retrohepatic inferior vena cava and hepatic veins, and inferior vena cava--atrial shunting is the operation of choice for patients with occlusion of the inferior vena cava and patency of the hepatic veins. Membranotomy is used for patients with inferior vena cava webbing, and mesocaval shunting is used for patients with intrahepatic venous occlusion only.(ABSTRACT TRUNCATED AT 250 WORDS)
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3712
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Eberhard WL, Chen Z. Lidar discrimination of multiple fluorescent tracers of atmospheric motions. APPLIED OPTICS 1989; 28:2996-3007. [PMID: 20555642 DOI: 10.1364/ao.28.002996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
An analytical study demonstrates the feasibility of simultaneous lidar measurement and discrimination of multiple fluorescent particle tracers of air motions. Equations are presented for evaluating signal-to-noise ratio and interfering signals. Matrix methods can solve for the concentrations of several tracers from simultaneous measurements in at least as many spectral receiver channels, even when fluorescence spectra overlap. Two example systems, one with crosstalk and another without, are evaluated for accuracy in the presence of shot noise and calibration errors. Potential applications include observing the structure of complex flows and measuring the effect of release location on atmospheric transport and dispersion.
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3713
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Kim YD, Tsang MB, Gelbke CK, Lynch WG, Carlin N, Chen Z, Fox R, Gong WG, Murakami T, Nayak TK, Ronningen RM, Xu HM, Zhu F, Bauer W, Sobotka LG, Stracener D, Sarantites DG, Majka Z, Abenante V, Griffin H. Multifragment emission observed for the reaction 36Ar + 238U at E/A=35 MeV. PHYSICAL REVIEW LETTERS 1989; 63:494-497. [PMID: 10041089 DOI: 10.1103/physrevlett.63.494] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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3714
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Linton JP, Yen JY, Selby E, Chen Z, Chinsky JM, Liu K, Kellems RE, Crouse GF. Dual bidirectional promoters at the mouse dhfr locus: cloning and characterization of two mRNA classes of the divergently transcribed Rep-1 gene. Mol Cell Biol 1989; 9:3058-72. [PMID: 2674679 PMCID: PMC362775 DOI: 10.1128/mcb.9.7.3058-3072.1989] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The mouse dihydrofolate reductase gene (dhfr) is a housekeeping gene expressed under the control of a promoter region embedded in a CpG island--a region rich in unmethylated CpG dinucleotides. A divergent transcription unit exists immediately upstream of the dhfr gene which is coamplified with dhfr in some but not all methotrexate-resistant cell lines. We show that the promoter region for this gene pair consists of two bidirectional promoters, a major and minor promoter, which are situated within a 660-base-pair region upstream of the dhfr ATG translation initiation codon. The major promoter controls over 90% of dhfr transcription, while the minor promoter directs the transcription of the remaining dhfr mRNAs. The major promoter functions bidirectionally, transcribing a divergent 4.0-kilobase poly(A) mRNA (class A) in the direction opposite that of dhfr transcription. The predicted protein product of this mRNA is 105 kilodaltons. The minor promoter also functions bidirectionally, directing the transcription of at least two divergent RNAs (class B). These RNAs, present in quantities approximately 1/10 to 1/50 that of the class A mRNAs, are 4.4- and 1.6-kilobase poly(A) mRNAs. cDNAs representing both class A and class B mRNAs have been cloned from a mouse fibroblast cell line which has amplified the dhfr locus (3T3R500). DNA sequence analysis of these cDNAs reveals that the class A and class B mRNAs share, for the most part, the same exons. On the basis of S1 nuclease protection analysis of RNA preparations from several mouse tissues, both dhfr and divergent genes showed similar levels of expression but did show some specificity in start site utilization. Computer homology searches have revealed sequence similarity of the divergent transcripts with bacterial genes involved in DNA mismatch repair, and we therefore have named the divergently transcribed gene Rep-1.
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3715
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Chen Z, Evans DA, Vasconcelos A. Use of tissue culture to bypass wheat hybrid necrosis. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 1989; 78:57-60. [PMID: 24227030 DOI: 10.1007/bf00299753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/1988] [Accepted: 03/17/1989] [Indexed: 06/02/2023]
Abstract
Hybrid necrosis in wheat is a barrier to gene transfer in wheat breeding practice. It is based on two complementary genes, Ne1 and Ne2. Recovery mutants (Re1, Re2 and Re3) which can grow to maturity were recovered from immature embryo cultures of necrotic hybrids between T. aestivum and T. durum. Cytological observation demonstrated that Re1 had 34 chromosomes instead of 35. This indicated that one of the chromosomes carrying the Ne genes was lost. Genetic study suggested that for Re1, the lost chromosome was chromosome 5B of the durum parental line. Re mutants are male sterile but can be maintained through a young ear culture method. Re mutants could be successfully pollinated by either parental line and the BC1 progeny is partially fertile. Re mutants were repeatedly induced in about 1% of the regenerated plants from immature embryo culture. This technique provides a practical way to bypass hybrid necrosis.
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3716
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Chen Z, Engberg G. The rat nucleus paragigantocellularis as a relay station to mediate peripherally induced central effects of nicotine. Neurosci Lett 1989; 101:67-71. [PMID: 2771156 DOI: 10.1016/0304-3940(89)90442-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Previous electrophysiological studies have shown that intravenously administered nicotine in low doses indirectly excites noradrenergic locus coeruleus (LC) neurons. In the present study this effect of nicotine was attenuated (to about 25% of control response) by injection of lidocaine into the nucleus paragigantocellularis (PGi) whereas injection into the nucleus prepositus hypoglossi (PrH) had no effect in this regard. Whereas the basal firing rate of LC neurons was not affected by lidocaine injection into the PGi, more than 50% of the LC neurons displayed increased firing rate following lidocaine injection into the PrH. It is suggested that the peripherally induced effect of nicotine on LC neurons is indirectly mediated via activation of the PGi.
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3717
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Weng MH, Chen Z. The therapeutic effect of mulberry in the treatment of constipation and insomnia in the elderly. J TRADIT CHIN MED 1989; 9:93-4. [PMID: 2779283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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3718
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Chen Z, Sheng P. Optical effects of multipole interaction in aggregated structures: Rigorous scattering solution for a periodic chain of cylinders. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 39:9816-9827. [PMID: 9947755 DOI: 10.1103/physrevb.39.9816] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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3719
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Xiao GH, Lai FY, Chen Z, Chen ZH, Lu BQ. [Fragile X syndrome complicated by autism]. ZHONGHUA YI XUE ZA ZHI 1989; 69:284-5. [PMID: 2804742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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3720
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Loiseau P, Guglielmi P, Le Paslier D, MacIntyre E, Gessain A, Bories JC, Flandrin G, Chen Z, Sigaux F. Rearrangements of the T cell receptor delta gene in T acute lymphoblastic leukemia cells are distinct from those occurring in B lineage acute lymphoblastic leukemia and preferentially involve one V delta gene segment. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1989; 142:3305-11. [PMID: 2523429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Rearrangement of the TCR-delta gene was studied using J delta, C delta, and V delta probes in 61 cases of acute lymphoblastic leukemia (ALL) and several cases of chronic lymphoid neoplasms to define the specificity and the diversity of rearrangements occurring at the delta locus. TCR-delta rearrangements or deletions were found in all T (33 cases) and B lineage (28 cases) ALL but not in any case of B cell chronic proliferations (13 cases). The restriction patterns of rearrangement were clearly distinct between T and B ALL and use of one V delta probe showed that rearrangement of the V delta IDP2 gene segment which is also productively rearranged in the Peer cell line, occurred frequently in T-ALL but never in B lineage ALL. Studies of WT31 and delta TCS1 antibody reactivity showed that at least 4 of 13 CD3+ T-ALL cases expressed the delta protein. CD4 and/or CD8 Ag expression were observed in some of the gamma delta expressing T-ALL. These data show that particular TCR-delta gene rearrangements occur in neoplastic early B cells and that the combinatorial diversity of TCR-delta rearrangements in T cells is higher than initially expected. In addition this study shows that an important proportion of CD3 positive T-ALL cases express the gamma delta heterodimer.
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MESH Headings
- Antigens, Differentiation, T-Lymphocyte/analysis
- Antigens, Differentiation, T-Lymphocyte/genetics
- Burkitt Lymphoma/genetics
- CD3 Complex
- CD8 Antigens
- Cell Line
- Chromosome Deletion
- Gene Rearrangement, T-Lymphocyte
- Humans
- Immunoglobulin Variable Region/genetics
- Leukemia-Lymphoma, Adult T-Cell/classification
- Leukemia-Lymphoma, Adult T-Cell/genetics
- Phenotype
- Receptors, Antigen, T-Cell/analysis
- Receptors, Antigen, T-Cell/genetics
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3721
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Loiseau P, Guglielmi P, Le Paslier D, MacIntyre E, Gessain A, Bories JC, Flandrin G, Chen Z, Sigaux F. Rearrangements of the T cell receptor delta gene in T acute lymphoblastic leukemia cells are distinct from those occurring in B lineage acute lymphoblastic leukemia and preferentially involve one V delta gene segment. THE JOURNAL OF IMMUNOLOGY 1989. [DOI: 10.4049/jimmunol.142.9.3305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Rearrangement of the TCR-delta gene was studied using J delta, C delta, and V delta probes in 61 cases of acute lymphoblastic leukemia (ALL) and several cases of chronic lymphoid neoplasms to define the specificity and the diversity of rearrangements occurring at the delta locus. TCR-delta rearrangements or deletions were found in all T (33 cases) and B lineage (28 cases) ALL but not in any case of B cell chronic proliferations (13 cases). The restriction patterns of rearrangement were clearly distinct between T and B ALL and use of one V delta probe showed that rearrangement of the V delta IDP2 gene segment which is also productively rearranged in the Peer cell line, occurred frequently in T-ALL but never in B lineage ALL. Studies of WT31 and delta TCS1 antibody reactivity showed that at least 4 of 13 CD3+ T-ALL cases expressed the delta protein. CD4 and/or CD8 Ag expression were observed in some of the gamma delta expressing T-ALL. These data show that particular TCR-delta gene rearrangements occur in neoplastic early B cells and that the combinatorial diversity of TCR-delta rearrangements in T cells is higher than initially expected. In addition this study shows that an important proportion of CD3 positive T-ALL cases express the gamma delta heterodimer.
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3722
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Chen Z, Loiseau P, Bories JC, Bensussan A, Sigaux F. Rearranging sequence located in the intron of the human T cell receptor gamma chain gene constant region. Eur J Immunol 1989; 19:637-42. [PMID: 2543583 DOI: 10.1002/eji.1830190410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Human T cell rearranging gamma genes encode membrane proteins which are expressed by a minor subset of T cells. Extensive studies have shown that TcR gamma gene rearrangements result from V gamma-J gamma recombinations. Here we analyze an unusual rearrangement involving a non-translatable sequence flanked by heptamer and nonamer signals in a Ti alpha/beta-positive T cell clone (JF1). This sequence, designated here as I gamma RS, is distinct from V, D or J elements. It is located in the first intron of the first constant region (C gamma 1) and homologous sequences are conserved in C gamma 2 introns. In JF1 cells the I gamma RS is juxtaposed to the J gamma 2 segment downstream to a V gamma 10-J gamma 1 rearrangement. The use of a cryptic splicing site induced JF1 cells to produce an aberrant large-sized transcript containing the I gamma RS 3' to the first exon of C gamma 1. Such a rearrangement occurring downstream to an inframe V gamma-J gamma junction may induce premature arrest of translation and lack of the C-terminal part of C gamma involved in gamma-protein assembly.
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MESH Headings
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor
- Humans
- Introns
- Molecular Sequence Data
- RNA, Messenger/genetics
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell, alpha-beta
- Receptors, Antigen, T-Cell, gamma-delta
- Restriction Mapping
- T-Lymphocytes/physiology
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3723
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Chen SJ, Chen Z, Hillion J, Grausz D, Loiseau P, Flandrin G, Berger R. Ph1-positive, bcr-negative acute leukemias: clustering of breakpoints on chromosome 22 in the 3' end of the BCR gene first intron. Blood 1989; 73:1312-5. [PMID: 2930840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
About 50% of the Philadelphia-positive acute leukemias undergo molecular rearrangements outside the now classical bcr sequence (or M-BCR-1) rearranged in chronic myeloid leukemia (CML). Most of the breakpoints on chromosome 22 have been shown to be clustered in a 10.8-kb region of the first intron of the BCR gene (called bcr2 or m-BCR-1). In this report we examined two cases of Ph1 acute lymphoblastic leukemia in adult patients that exhibited breakpoints in a 5-kb segment of the BCR gene first intron, 16 kb upstream of the previously described cluster, suggesting the possibility of a second minor breakpoint cluster. In addition, the breakpoints on chromosome 9 were located in a region just 5' of the c-abl exon la.
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3724
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Valdez BC, Chen Z, Sosa MG, Younathan ES, Chang SH. Human 6-phosphofructo-1-kinase gene has an additional intron upstream of start codon. Gene 1989; 76:167-9. [PMID: 2526044 DOI: 10.1016/0378-1119(89)90019-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A 6-phosphofructo-1-kinase-coding gene (pfk) has been purified from a human genomic library cloned in the lambda EMBL4 phage vector. This clone contains the nontranslated 5' flanking region of the human muscle pfk gene. Comparison of the nucleotide sequence determined by us with that of the human muscle pfk cDNA [Nakajima et al., FEBS Lett. 223 (1987) 113-116] indicates the presence of an additional intron extending from nucleotide (nt) -97 to -9 upstream of the ATG start codon. Furthermore, the human muscle pfk gene is more AT-rich than the rabbit gene. The available sequence of the two cDNAs shows 256 nt differences. Surprisingly, 71% of these sites are A's and T's in the human cDNA and C's and G's in the rabbit gene.
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3725
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Chen Z, Romrell LJ, Allen CM. Dehydrodolichyl diphosphate synthase in Sertoli and spermatogenic cells of prepuberal rats. J Biol Chem 1989; 264:3849-53. [PMID: 2645280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The specific activity of 2,3-dehydrodolichyl diphosphate synthase in homogenates of protease-treated seminiferous tubules, enriched spermatogenic cells, and Sertoli cells changed as a function of the age of prepuberal rats. The highest enzymatic activity occurred in each case in 23-day-old rats. Homogenates of pachytene spermatocytes, spermatids, or Sertoli cells had higher synthase activity than a whole testicular homogenate prepared by protease treatment of tubules. Enzymatic activity in pachytene spermatocytes expressed per mg of protein was about 1.7-fold higher than in spermatids, 5.3-fold higher than in spermatogonia, and about 8.3-fold higher than in spermatozoa. Therefore, the increase in spermatogenic cell synthase before day 23 can be accounted for by the appearance of the pachytene spermatocytes. Enzymatic activity decreased remarkably after the differentiation of spermatids into spermatozoa. Synthase activity in enriched Sertoli cell preparations was 1.5-2.3-fold higher than in spermatogenic cell preparations between days 15 and 30. Therefore, both spermatogenic cells and Sertoli cells contribute to changes in the enzymatic activity in seminiferous tubules during development. These changes may be important in regulating the availability of dolichyl phosphate for glycoprotein synthesis during early stages of differentiation.
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