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P E Messier

Publications and source records attributed to P E Messier.

At least 37 records · Page 2Linked to original sources
PubMed1976

Effects of formamide on neuroepithelial cells and on interkinetic nuclear migration in the chick embryo.

Young chicken embryos were incubated on media containing formamide at concentrations of 0-1, 0-25, 0-31, 0-37, 0-43 and 0-5 M. In the neuroepithelium of these embryos we found that (1) the 0-1 M concentration had no detectable effect, (2) the 0-25 M concentration only affected mitosis which was blocked in metaphase so that mitotic figures accumulated near the neurocoele, (3) 0-31 M formamide totally inhibited interkinetic nuclear migration and affected only slightly the cell asymmetry, (4) the 0-37 M concentration considerably reduced the amount of cytoplasmic microtubules and that the cells became round, (5) at 0-43 M formamide, all microtubules had disappeared and all cells were spherical, (6) 0-5 M formamide all cells were spherical, detached from one another and the epithelium had lost its usual characteristics. Our results on exposure of the cells to low temperature (2 degrees C) suggest that formamide directly affects microtubules. All the effects observed at concentrations up to 0-43 M formamide are reversible.

Animals↗
PubMed1975

[Neurulation and interkinetic nuclear migration in the chick embryo (author's transl)].

Neurulation and interkinetic nuclear migration was studied in cells of the forming neural tube of chick embryos submitted to a variety of treatments. Our results show that cytochalasin B (5 mug/ml) does not protect microtubules against disruption occurring after 3 h at 2 degrees C nor does it prevent their repolymerization once they are cold-disrupted. However, db-cAMP protects microtubules against such cold disruption. We indicate that the inhibitory effect of cytochalasin B on interkinetic nuclear migration cannot be ascribed to an effect on microtubules.

Animals↗