<it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it>
<p>Abstract</p> <p>Background</p> <p>High levels of <it>Hepatoma Up-Regulated Protein </it>(<it>HURP</it>) and <it>Tousled-Like Kinase </it>(<it>TLK</it>) transcripts are found in hepatocellular carcinoma. <it>HURP &...
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| Format: | Article |
| Language: | English |
| Published: |
BMC
2009-06-01
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| Series: | Journal of Biomedical Science |
| Online Access: | http://www.jbiomedsci.com/content/16/1/51 |
| _version_ | 1818163083904811008 |
|---|---|
| author | Huang Hsiao-Yu Chiang Chuen-Sheue Li Hsing-Hsi Liaw Gwo-Jen |
| author_facet | Huang Hsiao-Yu Chiang Chuen-Sheue Li Hsing-Hsi Liaw Gwo-Jen |
| author_sort | Huang Hsiao-Yu |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>High levels of <it>Hepatoma Up-Regulated Protein </it>(<it>HURP</it>) and <it>Tousled-Like Kinase </it>(<it>TLK</it>) transcripts are found in hepatocellular carcinoma. <it>HURP </it>overexpression induces anchorage-independent growth of 293-T cells and enhances a rough-eye phenotype resulting from <it>tlk </it>overexpression in <it>Drosophila</it>. In addition, both HURP and Mars, a <it>Drosophila </it>HURP sequence homologue, promote polymerization of mitotic spindles. Thus, the genetic interaction of <it>mars </it>with <it>tlk </it>might be required for accurate chromosome segregation.</p> <p>Methods</p> <p>To reveal whether chromosome fidelity was decreased, the frequency of gynandromorphy, an individual with both male and female characteristics, and of non-disjunction were measured in the progeny from parents with reduced <it>mars </it>and/or <it>tlk </it>activities and analyzed by Student's <it>t</it>-test. To show that the genetic interaction between <it>mars </it>and <it>tlk </it>is epistatic or parallel, a cytological analysis of embryos with either reduced or increased activities of <it>mars </it>and/or <it>tlk </it>was used to reveal defects in mitotic-spindle morphology and chromosome segregation.</p> <p>Results</p> <p>A significant but small fraction of the progeny from parents with reduced <it>mars </it>activity showed gynandromorphy and non-disjunction. Results of cytological analysis revealed that the decrease in chromosome fidelity was a result of delayed polymerization of the mitotic spindle, which led to asynchronous chromosome segregation in embryos that had reduced <it>mars </it>activity. By removing one copy of <it>tousled-like kinase </it>(<it>tlk</it>) from flies with reduced <it>mars </it>activity, chromosome fidelity was further reduced. This was indicated by an increased in the non-disjunction rate and more severe asynchrony. However, the morphology of the mitotic spindles in the embryos at metaphase where both gene activities were reduced was similar to that in <it>mars </it>embryos. Furthermore, <it>tlk </it>overexpression did not affect the morphology of the mitotic spindles and the cellular localization of Mars protein.</p> <p>Conclusion</p> <p>Chromosome fidelity in progeny from parents with reduced <it>mars </it>and/or <it>tlk </it>activity was impaired. The results from cytological studies revealed that <it>mars </it>and <it>tlk </it>function in parallel and that a balance between <it>mars </it>activity and <it>tlk </it>activity is required for cells to progress through mitosis correctly, thus ensuring chromosome fidelity.</p> |
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| institution | Directory Open Access Journal |
| issn | 1021-7770 1423-0127 |
| language | English |
| last_indexed | 2024-12-11T16:43:56Z |
| publishDate | 2009-06-01 |
| publisher | BMC |
| record_format | Article |
| series | Journal of Biomedical Science |
| spelling | doaj.art-9264a6ab85c04dab8bb1301233bfe3c72022-12-22T00:58:16ZengBMCJournal of Biomedical Science1021-77701423-01272009-06-011615110.1186/1423-0127-16-51<it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it>Huang Hsiao-YuChiang Chuen-SheueLi Hsing-HsiLiaw Gwo-Jen<p>Abstract</p> <p>Background</p> <p>High levels of <it>Hepatoma Up-Regulated Protein </it>(<it>HURP</it>) and <it>Tousled-Like Kinase </it>(<it>TLK</it>) transcripts are found in hepatocellular carcinoma. <it>HURP </it>overexpression induces anchorage-independent growth of 293-T cells and enhances a rough-eye phenotype resulting from <it>tlk </it>overexpression in <it>Drosophila</it>. In addition, both HURP and Mars, a <it>Drosophila </it>HURP sequence homologue, promote polymerization of mitotic spindles. Thus, the genetic interaction of <it>mars </it>with <it>tlk </it>might be required for accurate chromosome segregation.</p> <p>Methods</p> <p>To reveal whether chromosome fidelity was decreased, the frequency of gynandromorphy, an individual with both male and female characteristics, and of non-disjunction were measured in the progeny from parents with reduced <it>mars </it>and/or <it>tlk </it>activities and analyzed by Student's <it>t</it>-test. To show that the genetic interaction between <it>mars </it>and <it>tlk </it>is epistatic or parallel, a cytological analysis of embryos with either reduced or increased activities of <it>mars </it>and/or <it>tlk </it>was used to reveal defects in mitotic-spindle morphology and chromosome segregation.</p> <p>Results</p> <p>A significant but small fraction of the progeny from parents with reduced <it>mars </it>activity showed gynandromorphy and non-disjunction. Results of cytological analysis revealed that the decrease in chromosome fidelity was a result of delayed polymerization of the mitotic spindle, which led to asynchronous chromosome segregation in embryos that had reduced <it>mars </it>activity. By removing one copy of <it>tousled-like kinase </it>(<it>tlk</it>) from flies with reduced <it>mars </it>activity, chromosome fidelity was further reduced. This was indicated by an increased in the non-disjunction rate and more severe asynchrony. However, the morphology of the mitotic spindles in the embryos at metaphase where both gene activities were reduced was similar to that in <it>mars </it>embryos. Furthermore, <it>tlk </it>overexpression did not affect the morphology of the mitotic spindles and the cellular localization of Mars protein.</p> <p>Conclusion</p> <p>Chromosome fidelity in progeny from parents with reduced <it>mars </it>and/or <it>tlk </it>activity was impaired. The results from cytological studies revealed that <it>mars </it>and <it>tlk </it>function in parallel and that a balance between <it>mars </it>activity and <it>tlk </it>activity is required for cells to progress through mitosis correctly, thus ensuring chromosome fidelity.</p>http://www.jbiomedsci.com/content/16/1/51 |
| spellingShingle | Huang Hsiao-Yu Chiang Chuen-Sheue Li Hsing-Hsi Liaw Gwo-Jen <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> Journal of Biomedical Science |
| title | <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> |
| title_full | <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> |
| title_fullStr | <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> |
| title_full_unstemmed | <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> |
| title_short | <it>mars </it>and <it>tousled-like kinase </it>act in parallel to ensure chromosome fidelity in <it>Drosophila</it> |
| title_sort | it mars it and it tousled like kinase it act in parallel to ensure chromosome fidelity in it drosophila it |
| url | http://www.jbiomedsci.com/content/16/1/51 |
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