Abstract
SUMMARYThe effect of RNA synthesis inhibition on the progress of mitosis was studied in meristematic cells of Allium cepa at the ultrastructural level. The continuous treatment with 3'AdR and EB on cells which are in the beginning of mitosis, causes the persistence of the nuclear envelope (GONZALEZ-FERNANDEZ et al. 1970) without blocking the chromosomal cycle (RISUENO et al. 1975). In the case of EB there are ruptures in some points of the nuclear envelope but with 3'AdR it is still intact.The ultrastructural analysis of 3'AdR treated cells shows a greater chromosomal condensation than in controls, and a structural modification of chromosomes, which acquire an U form.In the case of EB treatment the chromosomal condensation is similar to those in untreated cells. In both cases, the mitotic chromosomes show connections between each other and with the nuclear envelope. These connections are formed by chromosomal fibres, frameworked during the chromosomal condensation in prophase. Thus, the inhibition of RNA ...
Highlights
Some authors have noted the effect of the inhibition of RNA synthesis on the evolution of mitosis (GIMENEZ-MARTIN et al 1971; GONZALEZ-FERNANDEZ et al 1970 )
In this study we shall describe at the ultrastructural level the action of continuous treatment with two antimetabolites which affect RNA synthesis: cordycepin (3'AdR) and ethidium bromide (EB), on the evolution of mitosis, in meristematic cells of Allium cepa that begin prophase· in the presence of these drugs
The nuclear envelope remains fully visible during prophase and metaphase (Figs. 13, 14)
Summary
Some authors have noted the effect of the inhibition of RNA synthesis on the evolution of mitosis (GIMENEZ-MARTIN et al 1971; GONZALEZ-FERNANDEZ et al 1970 ). The effect of RNA synthesis inhibition on cells initiating mitosis was described as a blocking of their division cycle in prophase. Blocking the nuclear envelope breakdown prevents the cells from reaching metaphase (GONZALEZ-FERNANDEZ et al 1970). In this study we shall describe at the ultrastructural level the action of continuous treatment with two antimetabolites which affect RNA synthesis: cordycepin (3'AdR) and ethidium bromide (EB), on the evolution of mitosis, in meristematic cells of Allium cepa that begin prophase· in the presence of these drugs. The modifications observed in the mitosis of treated cells will be analyzed in relation to the nucleolar and chromosomal cycles of untreated mitotic cells
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
