Probing microtubule polymerisation state at single kinetochores during metaphase chromosome motion.
Probing microtubule polymerisation state at single kinetochores during metaphase chromosome motion.
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DOI：
10.1242/jcs.168682
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发表时间：
2015-05-15
影响因子：
4
通讯作者：
Burroughs NJ
中科院分区：
文献类型：
--
作者：
Armond JW;Vladimirou E;Erent M;McAinsh AD;Burroughs NJ
着丝点调节附着的微管束（着丝点纤维，k -纤维）的动力学，以产生有丝分裂中染色体运动所需的力。目前的模型表明，向极移动的着丝点附着在解聚合的k -纤维上，而反向极移动的着丝点附着在聚合的k -纤维上。k纤维中单个微管的动力学如何与极向运动和反极运动相关，目前尚不清楚。为了研究这一点，我们开发了一种结合计算图像分析的活细胞成像方法，允许egfp标记的EB3（也称为MAPRE3）在数千个个体中期着丝点进行极性和反极性运动时进行量化。令人惊讶的是，我们发现k -纤维是不相干的，包含聚合和解聚合的微管-对反极移动的着丝点具有小的聚合偏倚。k -纤维也显示出EB3强度的爆发，主要是在反极移动的着丝点上，相当于更连贯的聚合，这与更有规律的振荡有关。在失去激酶-13后，爆发频率和聚合偏倚降低，而失去激酶-8则升高聚合偏倚。因此，着丝点积极地设置k纤维中微管聚合动力学的平衡，同时对微管聚合的波动保持很大的鲁棒性。
Kinetochores regulate the dynamics of attached microtubule bundles (kinetochore-fibres, K-fibres) to generate the forces necessary for chromosome movements in mitosis. Current models suggest that poleward-moving kinetochores are attached to depolymerising K-fibres and anti-poleward-moving kinetochores to polymerising K-fibres. How the dynamics of individual microtubules within the K-fibre relate to poleward and anti-poleward movements is poorly understood. To investigate this, we developed a live-cell imaging assay combined with computational image analysis that allows eGFP-tagged EB3 (also known as MAPRE3) to be quantified at thousands of individual metaphase kinetochores as they undergo poleward and anti-poleward motion. Surprisingly, we found that K-fibres are incoherent, containing both polymerising and depolymerising microtubules – with a small polymerisation bias for anti-poleward-moving kinetochores. K-fibres also display bursts of EB3 intensity, predominantly on anti-poleward-moving kinetochores, equivalent to more coherent polymerisation, and this was associated with more regular oscillations. The frequency of bursts and the polymerisation bias decreased upon loss of kinesin-13, whereas loss of kinesin-8 elevated polymerisation bias. Thus, kinetochores actively set the balance of microtubule polymerisation dynamics in the K-fibre while remaining largely robust to fluctuations in microtubule polymerisation.
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DOI：
10.1083/jcb.122.4.859
发表时间：
1993-08
期刊：
The Journal of cell biology
影响因子：
--
作者：
Skibbens RV;Skeen VP;Salmon ED
通讯作者：
Salmon ED
影响因子：
6.1
作者：
McIntosh, J. Richard;Molodtsov, Maxim I.;Ataullakhanov, Fazly I.
通讯作者：
Ataullakhanov, Fazly I.
影响因子：
16
作者：
Hunter, AW;Caplow, M;Howard, J
通讯作者：
Howard, J
DOI：
10.1083/jcb.200909005
发表时间：
2010-03-08
期刊：
The Journal of cell biology
影响因子：
--
作者：
Jaqaman K;King EM;Amaro AC;Winter JR;Dorn JF;Elliott HL;McHedlishvili N;McClelland SE;Porter IM;Posch M;Toso A;Danuser G;McAinsh AD;Meraldi P;Swedlow JR
通讯作者：
Swedlow JR
影响因子：
9.2
作者：
Mayr, Monika I.;Huemmer, Stefan;Mayer, Thomas U.
通讯作者：
Mayer, Thomas U.