Action of Ribonuclease on Living Cells in vitro and Synthesis of Deoxyribonucleic Acid

Firket, H; Chevremont-Comhaire, S; Chèvremont, M

doi:10.1038/1761075a0

Cited by 26 publications

(5 citation statements)

References 2 publications

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“…Such a mechanism has been described for the escape of pancreatic enzymes from zymogen granules into the cytoplasm of acinar cells (25). Ribonuclease is thought to enter several plant and animal cells by a comparable mechanism (8,17,24). In spite of these observations, the process of direct passage of proteins through membranes is uncommon and poorly understood.…”

Section: Resultsmentioning

confidence: 99%

Interaction of cultured mammalian cells with [125I] diphtheria toxin

Bonventre¹,

Saelinger²,

Ivins³

et al. 1975

Infect Immun

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The characteristics of cell adsorption and pinocytotic uptake of diphtheria toxin by several mammalian cell types were studied. Purified toxin iodinated by a solid-state lactoperoxidase method provided preparations of high specific activity and unaltered biological activity. Diphtheria toxin-sensitive HEp-2 cells and guinea pig macrophage cultures were compared with resistant mouse L-929 cells. At 37 C the resistant cells in monolayer adsorbed and internalized

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Section: Resultsmentioning

confidence: 99%

Interaction of cultured mammalian cells with [125I] diphtheria toxin

Bonventre¹,

Saelinger²,

Ivins³

et al. 1975

Infect Immun

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“…Escape of toxin from pinocytic vesicles may occur when abnormally large amounts of toxin are pinocytized, and toxicity can be expressed (4). through the membrane has been described for the entrance of ribonuclease into plant and animal cells (8,19,28), and more recently Rothman (31) presented convincing arguments that protein transport in the pancreas proceeds through membranes rather than via vesiclemediated transport from compartment to compartment.…”

Section: Downloaded Frommentioning

confidence: 99%

Uptake of diphtheria toxin and its fragment A moiety by mammalian cells in culture

Saelinger¹,

Bonventre²,

Ivins³

et al. 1976

Infect Immun

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Evidence suggesting that diphtheria toxin reaches the cytoplasm of susceptible mammalian cells by two independent mechanisms is presented. A schematic model describing the two processes of toxin entry into the cell is developed. One process of toxin uptake considered to be physiologically significant is passage of the protein toxin through the plasma membrane. This most likely happens by binding of fragment B to receptors on the membrane and by subsequent toxinmembrane interaction so that ultimately fragment A, the enzymatically active moiety, is transported to the cell interior. This process, which ultimately leads to cessation of protein synthesis and cell death, involves a comparatively small number of toxin molecules. A second mechanism of toxin uptake is by classical pinocytosis. The majority of toxin taken into the cell is accomplished by this process. The fate of toxin taken into HEp-2 cells via pinocytosis is proteolysis by lysosomal enzymes. Thus, such vesicle-bound toxin is ordinarily not expressed biologically. Evidence suggesting that ammonium chloride provides total protection to diphtheria toxin-susceptible cells by preventing entry of toxin by the specific receptor-associated process is also provided; data showing that the ammonium salt immobilizes bound toxin on the plasma membrane of HEp-2 cells are presented. Finally, it is suggested that actively endocytic cells such as guinea pig macrophages interact with toxin in a significantly different manner than do nonphagocytic cells.

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“…Inhibition of cell division is noted in amphibian eggs (33,195), ascites tumor (193) amoebae (30), and tissue culture (55,116). With radioactive ribonuclease, autoradiography indicates an attachment to mitochondria and a block in oxidative phosphorylation similar to that produced by dinitrophenol (195).…”

Section: Structure and Chemistrymentioning

confidence: 93%

The Nucleic Acids

Cohn¹,

Volkin²

1957

Annu. Rev. Biochem.

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Previous reviews of this topic have summarized progress in the biosyn thesis (43), preparation (5), an d organic chemistry of nucleic acids and nucleotides (37). This essay is concerned with recent work that deals with nucleic acid structure, relation to physiological and metabolic events, and biological interventions. The large increase in the number of published papers is met by an attempt to summarize rather than to expound'in detail. STRUCTURE AND CHEMISTRYThe ability to prepare DNA from various sources in a more purified and less degraded form and ever-increasing apparent molecular weight (100), coupled with an appreciation of the roles of hydrogen bonding and internal charge distribution, which underlie the structure proposed by Watson & Crick (305), have inspired re-examinations of the physicochemical charac teristics of DNA with improved methodology.Titration.-More accurate determination of the pC' values of the effec tive groups in herring sperm DNA by Cox et al. (71) indicates essentially no phosphoryl titration in the neutral range, which eliminates consideration of secondary phosphoryl end groups and thus the need to invoke triply esteri fied phosphate. The hysteresis (difference between forward and backward titrations) in the titration of both herring sperm (71) and thymus (48, 166) DNA is ascribed to the normal (A to T, C to G) hydrogen bonding, which is eliminated at the extremes of pH, in accordance with theory. The increase in ultraviolet absorption (hyperchromic effect) and bathochromic shift in the spectrum after DNA has been carried to pH 2 or 13 is also in accord (191). It has been indicated by Cavalieri & Rosenberg (46) that the ac ceptance of a proton by guanine, the apparent pK of which varies consider ably with ionic strength (46, 166), may cause rearrangements in the purine that result in breaking both guanine-cytosine hydrogen bonds. The same reaction is held accountable by Cavalieri et al. for a spectrophotometrically 1 The survey of the literature pertaining to this review was completed in Novem ber, 1956.2 The following standard abbreviations are employed: RNA and DNA for the ribo-and deoxyribonucleic acids; A, G, C, MC, D, and T for adenine, guanine, cytosine, methylcytosine, uracil, and thymine; AMP, ADP, etc., for the corresponding nucleoside 5'-phosphates and -pyrophosphates; and TMV for tobacco mosaic virus.• Our thanks are due to Dr. K. Sebesta, of the Czechoslovak Academy of Sciences, for critical sum�ries of pertinent papers appearing in some forty journals of Central European countries. 4 Manuscript prepared under Contract No. W-7405-eng-26 for the Atomic Energy Commission. 491 Annu. Rev. Biochem. 1957.26:491-522. Downloaded from www.annualreviews.org Access provided by University of Western Ontario on 02/07/15. For personal use only. Quick links to online content Further ANNUAL REVIEWS

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Action of Ribonuclease on Living Cells in vitro and Synthesis of Deoxyribonucleic Acid

Cited by 26 publications

References 2 publications

Interaction of cultured mammalian cells with [125I] diphtheria toxin

Interaction of cultured mammalian cells with [125I] diphtheria toxin

Uptake of diphtheria toxin and its fragment A moiety by mammalian cells in culture

The Nucleic Acids

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