| Autor: |
Green, LC, Kalitsis, P, Chang, TM, Cipetic, M, Kim, JH, Marshall, O, Turnbull, L, Whitchurch, CB, Vagnarelli, P, Samejima, K, Earnshaw, WC, Choo, KHA, Hudson, DF |
| Jazyk: |
angličtina |
| Rok vydání: |
2012 |
| Předmět: |
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| Popis: |
© 2012. Published by The Company of Biologists Ltd In vertebrates, two condensin complexes exist, condensin I and condensin II, which have differing but unresolved roles in organizing mitotic chromosomes. To dissect accurately the role of each complex in mitosis, we have made and studied the first vertebrate conditional knockouts of the genes encoding condensin I subunit CAP-H and condensin II subunit CAP-D3 in chicken DT40 cells. Live-cell imaging reveals highly distinct segregation defects. CAP-D3 (condensin II) knockout results in masses of chromatin-containing anaphase bridges. CAP-H (condensin I)-knockout anaphases have a more subtle defect, with chromatids showing fine chromatin fibres that are associated with failure of cytokinesis and cell death. Super-resolution microscopy reveals that condensin-I-depleted mitotic chromosomes are wider and shorter, with a diffuse chromosome scaffold, whereas condensin-II-depleted chromosomes retain a more defined scaffold, with chromosomes more stretched and seemingly lacking in axial rigidity. We conclude that condensin II is required primarily to provide rigidity by establishing an initial chromosome axis around which condensin I can arrange loops of chromatin. This work was supported by an Australian Research Council discovery project [grant number DP110100784 to D.F.H., K.H.A.C. and W.C.E.]; National Health and Medical Research Council (NHMRC) project grants [APP1030358 and 546454]; an NHMRC RD Wright Fellowship to P.K.; an NHMRC Senior Research Fellowship to C.B.W.; an NHMRC Senior Principal Research Fellowship to K.H.A.C.; and by the Victorian Government’s Operational Infrastructure Support Program |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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