Immunohistochemical localization of glutamine synthetase in human liver

Glutamine synthetase (GS) of human liver was recognized with a polyclonal antibody to pig brain GS, but failed to stain with an antibody against rat liver GS. Using the latter antibody GS of human liver was shown to be localized within small rings of 1 to 3 hepatocytes surrounding the terminal hepatic venules. This pattern was analogous to that seen in rat and mouse liver.     

Immunohistochemical localization of glutamine synthetase in human liver

Glutamine synthetase (GS) of human liver was recognized with a polyclonal antibody to pig brain GS, but failed to stain with an antibody against rat liver GS. Using the latter antibody GS of human liver was shown to be localized within small rings of 1 to 3 hepatocytes surrounding the terminal hepatic venules. This pattern was analogous to that seen in rat and mouse liver.     

Presence of oncornavirus-like particles in the P388 murine leukemic cell line

Summary A culture of P388 murine lymphoblastoid cells has been shown to contain type C oncornavirus-like particles budding at the plasma membrane. Occasionally intracytoplasmic type A and immature type B particles were also observed by electron microscope techniques. The discovery of oncornavirus-like particles in the P388 cell line increases the utility of this neoplastic system for detecting potential antineoplastic agents.Supported by Contract NO1-CM-67048 from the Division of Cancer Treatment (DCT), National Cancer Institute (NCI), National Institutes of Health, Department of Health, Education, and Welfare. The fannie E. Rippel Foundation, Talley Industries, and the Phoenix Coca Cola Bottling Co. We are also grateful to Miss Linda M. Lange for technical assistance.     

Presence of oncornavirus-like particles in the P388 murine leukemic cell line

A culture of P388 murine lymphoblastoid cells has been shown to contain type C oncornavirus-like particles budding at the plasma membrane. Occasionally intracytoplasmic type A and immature type B particles were also observed by electron microscope techniques. The discovery of oncornavirus-like particles in the P388 cell line increases the utility of this neoplastic system for detecting potential antineoplastic agents.     

Interaction of extrinic fluoresence probes with E. coli glutamine synthetase

Summary Binding of 2-p-toluidinylnaphthalene-6-sulfonate (TNS) to adenylylated glutamine synthetase is cooperative and time-dependent, with 3 dye sites per subunit. In fluorescence polarization experiments TNS and pyrene butyrate give normalized Perrin plots that indicate a symmetrical arrangement of dye excited state dipoles, relative to the rotational axis of the oblate ellipsoid of the dodecameric native enzyme.Acknowledgment. Drs G. Weber and L. Brand are thanked for helpful comments on this work. — Supported in part by grants from the National Science Foundation (BMS 72-02165 and GU-3182). Portions of this work were presented in preliminary form at the 9th International Congress of Biochemistry, Stockholm, Sweden, July 1973.     

Murine type C endogenous virus expression in murine 129 teratocarcinoma cell line]

Murine type C viral information is detectable in the cellular genome of both differentiated and undifferentiated cell lines derived from 129 Mouse teratocarcinoma. Cytoplasmic RNA expression which is negligible in differentiated cells, is significantly higher in multipotential undifferentiated cells. Furthermore it was observed that in vitro differentiation of multipotent cells leads to a decrease of this expression.     

Inhibition of rat liver glutamine synthetase by phosphonic analogues of glutamic acid

Summary Analogues of glutamic acid, -methylglutamic acid and glutamine in which the -or -COOH groups are replaced by PO₃H₂ or P(O)(OH₃)OH functions competitively inhibit rat liver glutamine synthetase. The K₁ values are comparable to or lower than K_M for L-glutamate.This study was supported by grant R.1.9.     

Interaction of extrinsic fluorescent probes with E. coli glutamine synthetase.

Binding of 2-p-toluidinylnaphthalene-6-sulfonate (TNS) to adenylylated (E--11) glutamine synthetase is cooperative and time-dependent, with 3 dye sites per subunit. In fluorescence polarization experiments TNS and pyrene butyrate give normalized Perrin plots that indicate a symmetrical arrangement of dye excited state dipoles, relative to the rotational axis of the oblate ellipsoid of the dodecameric native enzyme.     

Purification and properties of glutamine synthetase I fromRhizobium sp. UMKL 20

Summary Glutamine synthetase I was purified fromRhizobium sp. UMKL 20 following polyethylene glycol precipitation. The enzyme had a subunit molecular weight of 58 kd. Apparent K_m values for ammonia and glutamate were 5.6 and 15.2 mM, respectively. Glutamine synthetase I activity was inhibited by several end products of glutamine metabolism. The purified enzyme was highly adenylylated (E _n ^– =8.5).Acknowledgment. I would like to thank Mr J. C. Lai for technical assistance. This work was carried out with the support of Vote F 153/79 from the University of Malaya.     

A comparative study of the regional distribution and structural attachment of cerebral glutamine synthetase

Résumé Des différences spécifiques de localisation régionale et d'attachement aux structures microsomiales de la glutamine-synthetase cérébrale sont décrites. L'administration intraventriculaire de doses non-convulsivantes de NaCl provoque chez le chat des modifications dans la fixation particulaire de l'enzyme aux structures corticales.

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This work was supported by grants from the United States Public Health Service Nos. He-1525 and NB-04549-01, and by the Institutional Grant to Tulane University IN-24E.     

Gene structure of the murine 2'-5'-oligoadenylate synthetase family

The 2'-5'-oligoadenylate synthetases (OASs) are members of a family of interferon-induced proteins playing an important role in the antiviral effect of interferons as well as being involved in apoptosis and control of cellular growth. Based on sequence data from the murine BAC clone (RP23-39M18), and a number of EST and IMAGE clones and the Celera Mouse database, we identified twelve Oas genes in the mouse genome, all localized to the chromosome 5F region. In contrast to the single OAS1 gene found in humans, we identified eight closely linked Oas1 genes in the murine genome, together with the genes of Oas2 and Oas3. Compared to the single OASL gene found in humans, two genes of OAS-like proteins, Oasl1 and Oasl2, were identified. All the putative genes seem to be transcribed. The exon/intron structures of the murine Oas genes were found to be identical to those of the human genes.     

A study on the antigenicity of a human cell line propagated in a heterologous medium

Résumé Des cellules HeLa cultivées dans un milieu qui contient du sérum de cheval, ont été transférées dans un milieu contenant du sérum humain. On a essayé, à différents moments, de détecter la présence de protéines de cheval dans les cellules transférées. Seules les cellules, qui ont été retirées du milieu hétérologue avant 48 h, donnent des réactions sérologiques positives.     

Acetylcholinesterase activity in anAedes aegypti cell line

Summary Considerable acetylcholinesterase (AChE) activity was detected in anAedes aegypti established cell line. The enzyme is blocked by 10^–6 M eserine sulfate, displays excess substrate inhibition and slowly hydrolyzes butyrylthiocholine. A 2-fold stimulation of AChE activity was shown after 2 days exposure to 3×10^–7 M -ecdysone. AChE activity found in the fresh medium is the contribution of the fetal calf serum portion. A direct relationship between levels of serum and the AChE activity in the cultured cells was demonstrated.Acknowledgment. I wish to thank Dr J. Peleg of the Israel Institute for Biological Research for providing the starting culture ofAedes aegypti cells.     

Antibody production in cultured lymphoblastoid cell line

Zusammenfassung Ein humaner Lymphoblastoiden-Zellstamm P3-J einer an Burkitt-Lymphoma Erkrankten wurde mit entsprechendenE.-coli-Bakterien eines Stammes RPMI Nr. 41 zusammen exponiert. Es muss angenommen werden, dass die Zellen vom Stamm P3-J Antikörper gegenE. coli oder RPMI Nr. 41 gebildet haben.