Cargando…
Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis
Myosin light chain kinase (MLCK) is thought to regulate the contractile activity in smooth and non-muscle cells, and may play an important role in controlling the reorganization of the actin-myosin cytoskeleton during cell division. To test this hypothesis we have microinjected the 61-kD catalytic f...
Formato: | Texto |
---|---|
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1991
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2289109/ https://www.ncbi.nlm.nih.gov/pubmed/1874791 |
_version_ | 1782152181667856384 |
---|---|
collection | PubMed |
description | Myosin light chain kinase (MLCK) is thought to regulate the contractile activity in smooth and non-muscle cells, and may play an important role in controlling the reorganization of the actin-myosin cytoskeleton during cell division. To test this hypothesis we have microinjected the 61-kD catalytic fragment of MLCK into mitotic cells, and examined the effects of unregulated MLCK activity on cell division. The microinjection of active 61 kD causes both a significant delay in the transit time from nuclear envelope breakdown to anaphase onset, and an increase in motile surface activity during and after metaphase. Control experiments with intact MLCK or with inactive catalytic fragment suggest that these effects are specifically induced by the unregulated myosin light chain kinase activity. Immunofluorescence analysis suggests that delays in mitosis are coupled to disruptions of spindle structures, while increased surface motility may be related to changes in the organization of actin and myosin at the cell cortex. Most importantly, despite the expression of strong phenotypes, 61 kD- injected cells still form functional cleavage furrows that progress through cytokinesis at rates identical to those of control cells. Together, these results suggest that the activity of MLCK can affect mitosis and cortical activities, however additional control mechanisms are likely involved in the regulation of cytokinesis. |
format | Text |
id | pubmed-2289109 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1991 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22891092008-05-01 Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis J Cell Biol Articles Myosin light chain kinase (MLCK) is thought to regulate the contractile activity in smooth and non-muscle cells, and may play an important role in controlling the reorganization of the actin-myosin cytoskeleton during cell division. To test this hypothesis we have microinjected the 61-kD catalytic fragment of MLCK into mitotic cells, and examined the effects of unregulated MLCK activity on cell division. The microinjection of active 61 kD causes both a significant delay in the transit time from nuclear envelope breakdown to anaphase onset, and an increase in motile surface activity during and after metaphase. Control experiments with intact MLCK or with inactive catalytic fragment suggest that these effects are specifically induced by the unregulated myosin light chain kinase activity. Immunofluorescence analysis suggests that delays in mitosis are coupled to disruptions of spindle structures, while increased surface motility may be related to changes in the organization of actin and myosin at the cell cortex. Most importantly, despite the expression of strong phenotypes, 61 kD- injected cells still form functional cleavage furrows that progress through cytokinesis at rates identical to those of control cells. Together, these results suggest that the activity of MLCK can affect mitosis and cortical activities, however additional control mechanisms are likely involved in the regulation of cytokinesis. The Rockefeller University Press 1991-09-01 /pmc/articles/PMC2289109/ /pubmed/1874791 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Articles Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title | Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title_full | Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title_fullStr | Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title_full_unstemmed | Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title_short | Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
title_sort | microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2289109/ https://www.ncbi.nlm.nih.gov/pubmed/1874791 |