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J Kates

Publications and source records attributed to J Kates.

25 records · Page 2Linked to original sources
PubMed1972

Induction of neuronal functions: acetylcholine-induced acetylcholinesterase activity in mouse neuroblastoma cells.

Addition of acetylcholine to growing cultures of mouse neuroblastoma cells induced a 37-fold increase in the specific activity of acetylcholinesterase (EC 3.1.1.7). Morphological changes, consisting of neurite-extensions, were also observed during the logarithmic phase of growth of cells stimulated with acetylcholine. A histochemical procedure for localization of acetylcholinesterase was used with the following results: (a) Cells differentiating by growth inhibition in serum-free medium do not stain positively for acetylcholinesterase, except when they have extended neurites, whereas all cells induced with acetylcholine, with or without neurites, stain positively for the enzyme. (b) The inverse relation between cell growth and induction of enzyme activity was demonstrated in nondividing cells at the center of a colony that do not incorporate thymidine into DNA and that stain positively for acetylcholinesterase, whereas actively dividing cells on the periphery of the colony do not stain for the enzyme. However, by addition of acetylcholine we were able to dissociate inhibition of cell growth from biochemical and morphological differentiation in mouse neuroblastoma cells.

Acetylcholine↗
PubMed1972

Detection of polyadenylic acid sequences in viral and eukaryotic RNA(polu(U)-cellulose columns-poly(U) filters-fiberglass-HeLa cells-bacteriophage T4).

A rapid and specific technique to detect polyriboadenylic acid sequences in RNA is described. The method depends upon the ability of RNAs that contain poly(A) sequences to associate specifically with poly(U) that has been immobilized on fiberglass filters by ultraviolet irradiation. A high proportion of the transcripts synthesized in vivo and in vitro from the vaccinia virus genome contain poly(A) sequences and bind to the poly(U) filters. Similarly, DNA-like RNA from the nucleus and from the cytoplasmic polyribosomes of HeLa cells is rich in species that bind to poly(U) filters. Poly(U) immobilized on cellulose powder is useful to make columns with a high capacity for the binding and purification of poly(A)-containing RNAs.

Adenine Nucleotides↗
PubMed1972

State of adenovirus 2 deoxyribonucleic acid in the nucleus and its mode of transcription: studies with isolated viral deoxyribonucleic acid-protein complexes and isolated nuclei.

Newly replicated adenovirus 2 deoxyribonucleic acid (DNA) can be isolated from the nucleus of HeLa cells by a gentle lysis procedure as a fairly homogeneous complex with a sedimentation of 73S. The viral DNA complex can be prepared completely free from host cell DNA. The viral complex is slightly active in ribonucleic acid (RNA) synthesis in vitro. Treatment of the complex with Pronase and sodium dodecyl sulfate converts the DNA to a form which sediments at 43S. Nuclei isolated from adeno-infected cells synthesize high-molecular-weight virus-specific RNA in vitro. Optimal RNA synthesis requires a divalent cation, preferentially manganese, and relatively high salt concentrations. The synthesis of virus-specific RNA by the isolated nuclei is strongly inhibited by low doses of alpha-amanitine. The latter experimental result is discussed in terms of the polymerase used to transcribe the adenovirus DNA in vivo.

Adenoviridae↗
PubMed1968

Synthesis and intracellular localization of vaccinia virus deoxyribonucleic acid-dependent ribonucleic acid polymerase.

The time course of vaccinia deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase synthesis and its intracellular localization were studied with virus-infected HeLa cells. Viral RNA polymerase activity could be meassured shortly after viral infection in the cytoplasmic fraction of infected cells in vitro. However, unless the cells were broken in the presence of the nonionic detergent Triton-X-100, no significant synthesis of new RNA polymerase was detected during the viral growth cycle. When cells were broken in the presence of this detergent, extensive increases in viral RNA polymerase activity were observed late in the infection cycle. The onset of new RNA polymerase synthesis was dependent on prior viral DNA replication. Fluorodeoxyuridine (5 x 10(-5)m) prevented the onset of viral polymerase synthesis. Streptovitacin A, a specific and complete inhibitor of protein synthesis in HeLa cells, prevented the synthesis of RNA polymerase. Thus, the synthesis of RNA polymerase is a "late" function of the virus. The newly synthesized RNA polymerase activity was primarily bound to particles which sedimented during high-speed centrifugation. These particles have been characterized by sucrose gradient centrifugation. A major class of active RNA polymerase particles were considerably "lighter" than whole virus in sucrose gradients. These particles were entirely resistant to the action of added pancreatic deoxyribonuclease, and they were not stimulated by added calf thymus primer DNA. It is concluded that these particles are not active in RNA synthesis in vivo, and that activation occurs as a result of detergent treatment in vitro.

Animals↗