Dynacortin facilitates polarization of chemotaxing cells
<p>Abstract</p> <p>Background</p> <p>Cell shape changes during cytokinesis and chemotaxis require regulation of the actin cytoskeletal network. Dynacortin, an actin cross-linking protein, localizes to the cell cortex and contributes to cortical resistance, thereby helpi...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2007-11-01
|
| Series: | BMC Biology |
| Online Access: | http://www.biomedcentral.com/1741-7007/5/53 |
| _version_ | 1818807283513032704 |
|---|---|
| author | Reichl Elizabeth M Musib Runa Xiong Yuan Kabacoff Cathryn Kim John Iglesias Pablo A Robinson Douglas N |
| author_facet | Reichl Elizabeth M Musib Runa Xiong Yuan Kabacoff Cathryn Kim John Iglesias Pablo A Robinson Douglas N |
| author_sort | Reichl Elizabeth M |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Cell shape changes during cytokinesis and chemotaxis require regulation of the actin cytoskeletal network. Dynacortin, an actin cross-linking protein, localizes to the cell cortex and contributes to cortical resistance, thereby helping to define the cell shape changes of cytokinesis. Dynacortin also becomes highly enriched in cortical protrusions, which are sites of new actin assembly.</p> <p>Results</p> <p>We studied the effect of dynacortin on cell motility during chemotaxis and on actin dynamics <it>in vivo </it>and <it>in vitro</it>. Dynacortin enriches with the actin, particularly at the leading edge of chemotaxing cells. Cells devoid of dynacortin do not become as polarized as wild-type control cells but move with similar velocities as wild-type cells. In particular, they send out multiple pseudopods that radiate at a broader distribution of angles relative to the chemoattractant gradient. Wild-type cells typically only send out one pseudopod at a time that does not diverge much from 0° on average relative to the gradient. Though <it>dynacortin</it>-deficient cells show normal bulk (whole-cell) actin assembly upon chemoattractant stimulation, dynacortin can promote actin assembly <it>in vitro</it>. By fluorescence spectroscopy, co-sedimentation and transmission electron microscopy, dynacortin acts as an actin scaffolder in which it assembles actin monomers into polymers with a stoichiometry of 1 Dyn<sub>2</sub>:1 actin under salt conditions that disfavor polymer assembly.</p> <p>Conclusion</p> <p>Dynacortin contributes to cell polarization during chemotaxis. By cross-linking and possibly stabilizing actin polymers, dynacortin also contributes to cortical viscoelasticity, which may be critical for establishing cell polarity. Though not essential for directional sensing or motility, dynacortin is required to establish cell polarity, the third core feature of chemotaxis.</p> |
| first_indexed | 2024-12-18T19:23:12Z |
| format | Article |
| id | doaj.art-563388086ad5496aba805cd5ec111d32 |
| institution | Directory Open Access Journal |
| issn | 1741-7007 |
| language | English |
| last_indexed | 2024-12-18T19:23:12Z |
| publishDate | 2007-11-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Biology |
| spelling | doaj.art-563388086ad5496aba805cd5ec111d322022-12-21T20:55:55ZengBMCBMC Biology1741-70072007-11-01515310.1186/1741-7007-5-53Dynacortin facilitates polarization of chemotaxing cellsReichl Elizabeth MMusib RunaXiong YuanKabacoff CathrynKim JohnIglesias Pablo ARobinson Douglas N<p>Abstract</p> <p>Background</p> <p>Cell shape changes during cytokinesis and chemotaxis require regulation of the actin cytoskeletal network. Dynacortin, an actin cross-linking protein, localizes to the cell cortex and contributes to cortical resistance, thereby helping to define the cell shape changes of cytokinesis. Dynacortin also becomes highly enriched in cortical protrusions, which are sites of new actin assembly.</p> <p>Results</p> <p>We studied the effect of dynacortin on cell motility during chemotaxis and on actin dynamics <it>in vivo </it>and <it>in vitro</it>. Dynacortin enriches with the actin, particularly at the leading edge of chemotaxing cells. Cells devoid of dynacortin do not become as polarized as wild-type control cells but move with similar velocities as wild-type cells. In particular, they send out multiple pseudopods that radiate at a broader distribution of angles relative to the chemoattractant gradient. Wild-type cells typically only send out one pseudopod at a time that does not diverge much from 0° on average relative to the gradient. Though <it>dynacortin</it>-deficient cells show normal bulk (whole-cell) actin assembly upon chemoattractant stimulation, dynacortin can promote actin assembly <it>in vitro</it>. By fluorescence spectroscopy, co-sedimentation and transmission electron microscopy, dynacortin acts as an actin scaffolder in which it assembles actin monomers into polymers with a stoichiometry of 1 Dyn<sub>2</sub>:1 actin under salt conditions that disfavor polymer assembly.</p> <p>Conclusion</p> <p>Dynacortin contributes to cell polarization during chemotaxis. By cross-linking and possibly stabilizing actin polymers, dynacortin also contributes to cortical viscoelasticity, which may be critical for establishing cell polarity. Though not essential for directional sensing or motility, dynacortin is required to establish cell polarity, the third core feature of chemotaxis.</p>http://www.biomedcentral.com/1741-7007/5/53 |
| spellingShingle | Reichl Elizabeth M Musib Runa Xiong Yuan Kabacoff Cathryn Kim John Iglesias Pablo A Robinson Douglas N Dynacortin facilitates polarization of chemotaxing cells BMC Biology |
| title | Dynacortin facilitates polarization of chemotaxing cells |
| title_full | Dynacortin facilitates polarization of chemotaxing cells |
| title_fullStr | Dynacortin facilitates polarization of chemotaxing cells |
| title_full_unstemmed | Dynacortin facilitates polarization of chemotaxing cells |
| title_short | Dynacortin facilitates polarization of chemotaxing cells |
| title_sort | dynacortin facilitates polarization of chemotaxing cells |
| url | http://www.biomedcentral.com/1741-7007/5/53 |
| work_keys_str_mv | AT reichlelizabethm dynacortinfacilitatespolarizationofchemotaxingcells AT musibruna dynacortinfacilitatespolarizationofchemotaxingcells AT xiongyuan dynacortinfacilitatespolarizationofchemotaxingcells AT kabacoffcathryn dynacortinfacilitatespolarizationofchemotaxingcells AT kimjohn dynacortinfacilitatespolarizationofchemotaxingcells AT iglesiaspabloa dynacortinfacilitatespolarizationofchemotaxingcells AT robinsondouglasn dynacortinfacilitatespolarizationofchemotaxingcells |