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Biomedical subjects

P H Fishman

Publications and source records attributed to P H Fishman.

At least 163 records · Page 9Linked to original sources
PubMed1974

Cholera toxin and cell growth: role of membrane gangliosides.

The binding of cholera toxin to three transformed mouse cell lines derived from the same parent strain, and the effects of the toxin on DNA synthesis and adenylate cyclase activity, vary in parallel with the ganglioside composition of the cells. TAL/N cells of early passage, which contain large quantities of gangliosides G(M3), G(M2), G(M1), and G(Dla), as well as the glycosyltransferases necessary for the synthesis of these gangliosides, bind the most cholera toxin and are the most sensitive to its action. TAL/N cells of later passage, which lack chemically detectable G(M1) and G(Dla) and which have no UDP-Gal:G(M2) galactosyltransferase activity, are intermediate in binding and response to the toxin. SVS AL/N cells, which lack G(M2) in addition to G(M1) and G(Dla) and which have little detectable UDP-GalNAc:G(M3)N-acetylgalactosaminyltransferase activity, bind the least amount of toxin. The SVS AL/N cells are the least responsive to inhibition of DNA synthesis and stimulation of adenylate cyclase activity by cholera toxin. Gangliosides (especially G(M1)), which appear to be the natural membrane receptors for cholera toxin, may normally have important roles in the regulation of cell growth and cAMP-mediated responses.

Adenylyl Cyclases↗
PubMed1974

Absence of a specific ganglioside galactosyltransferase in mouse cells transformed by murine sarcoma virus.

The ganglioside composition of a nonproducer subclone (derived from BALB/c 3T3 mouseembryo cells) transformed by Kirsten murine sarcoma virus was drastically altered compared to the nontransformed parental clone. The transformed clone was unable to synthesize the mono- and disialogangliosides, G(M1) and G(D1a), due to the complete absence of a specific galactosyltransferase. The lack of this enzyme activity was established by sensitive radiochemical and enzymological techniques in vivo and in vitro.

Animals↗