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G M Maniatis

Publications and source records attributed to G M Maniatis.

24 records · Page 2Linked to original sources
PubMed1974

Erythropoietic differentiation in colonies of cells transformed by Friend virus.

Cells transformed by Friend virus in liquid suspension culture respond to low concentrations of dimethylsulfoxide by initiating hemoglobin synthesis. The kinetics of appearance of such differentiated erythroid cells is consistent with either the induction of differentiation in a uniformly susceptible population of transformed cells or selection for the growth of a distinct erythropoietic subpopulation. The dimethylsulfoxide response of individual colonies of cells transformed by Friend virus grown in semisolid medium was studied in order to distinguish between these alternatives. The data do not support a selective effect of dimethylsulfoxide on the growth of a unique erythropoietic subpopulation; they indicate, rather, that the 745A strain of cells transformed by Friend virus consists of a relatively uniform population of dimethylsulfoxide-sensitive erythropoietic cells.

Animals↗
PubMed1973

Early stimulation of RNA synthesis by erythropoietin in cultures of erythroid precursor cells.

The effect of erythropoietin on cultured erythroid precursor cells from 13-day mouse-fetal livers was examined. Within 1 hr, erythropoietin causes a 2- to 3-fold stimulation of uridine incorporation into RNA by these cells. The types of RNA preferentially stimulated by erythropoietin during the first hour of exposure of the cells to the hormone include ribosomal RNAs and their precursors, as well as 4-5S RNA. No unique RNA species, not present in control cells, could be detected by sucrose gradient sedimentation or gel electrophoresis. Inhibition of protein synthesis for up to 1 hr does not abolish the stimulatory effect of erythropoietin on RNA synthesis, suggesting that the effect of the hormone on RNA synthesis is not mediated by a newly synthesized protein.

Animals↗
PubMedDate not supplied

Erythroid differentiation and the cell cycle: some implications from murine foetal and erythroleukemic cells.

On the basis of observations with (1) erythropoietin induced erythroid differentiation of foetal mouse liver proerythroblasts and (2) chemically induced expression of the erythroid program in MELC, it appears that DNA replication plays a critical role in the transition to haemoglobin formation. Erythropoietin acts selectively on proerythroblasts to stimulate first housekeeping RNA species (rRNA, tRNA), then cell proliferation and differentiation. In erythro-leukemia cells expression of the erythroid program is induced by a variety of polar compounds. DNA synthesis appears requisite to this transition to haemoglobin formation, The molecular site of action of inducing compounds is not established but it is suggested that one critical effect is on the structure of chromatin which occurs during DNA replication and results in the transcription of the erythropoietic gene program.

Animals↗