昆虫私生活

大象、老鼠以及我们人类均属脊椎动物。主要依靠巧妙的内骨架支持身体任意自由的活动，而节肢动物有个共同的特性，具有外骨骼，起着保护内脏，支持身体，着生肌肉等作用。无论哪一种动物都是经过胚胎发育等一系列过程而走向成熟，也就是说，从小到大由不完全趋于完全，但脊椎动物看似在渐渐长大，外观上并没有很大的变化，其实质是细胞分裂增值的结果，老的细胞死去，新的细胞诞生。     

植物生长发育中的感应性（二）——电化学波的信使传递与微丝微管的生理活动

（续1997年第6期第5页）1．2．4植物敏感度的变异性应该说，敏感植物和普通植物并没有严格的区别。中间存在着半敏感植物，如醉浆草（Oxaliscorniculata），要在多次的震动下，叶片才缓慢地下垂。文献中陆续与零星地报告出：普通（豆科、菊科、茄料等）植物中偶尔可以找到有类似动作电波传递。虽然它们在外观上表现不出快速的动作反应来。经过细致的检查却发现：它们接受电波的部位，会在气体代谢，生长发育，或是在原生质的运动、酶促反应上，作出及时的反应。如果电波来很频繁，在形态、生理、生化过程上甚至会引发长期的效应来。AW传递…     

驱动蛋白在一种新的微管动力中可能的生物学作用

细胞器沿着微管的转运能够用分离出的成份重新建立,从而对这一复杂的运动过程得以进行生物化学的剖析.这一技术途径己导致一个新颖的、普遍存在的、以微管为基础产生动力的蛋白质的提纯,称之为驱动蛋白(Kinesin,源于希腊语"运动").驱动蛋白的体外运动性质和免疫细胞化学定位提示,它可能作为细胞器转运和有丝分裂中微管依赖性运动的原动力而起作用.     

Aurora A orchestrates entosis by regulating a dynamic MCAK-TIP150 interaction

Entosis, a ceU-in-ceU process, has been implicated in the formation of aneuploidy associated with an aberrant cell division control. Microtubule plus-end-tracking protein TI P150 facilitates the loading of MCAK onto the microtubule plus ends and orchestrates micro- tubule plus-end dynamics during cell division. Here we show that TIP150 cooperates with MCAK to govern entosis via a regulatory cir- cuitry that involves Aurora A-mediated phosphorylation of MCAK. Our biochemical analyses show that MCAK forms an intra-molecular association, which is essential for TIP150 binding. Interestingly, Aurora A-mediated phosphorylation of MCAK modulates its intra-mo- lecular association, which perturbs the MCAK-TI P150 interaction in vitro and inhibits entosis in vivo. To probe if MCAK-TIP150 inter- action regulates microtubule plasticity to affect the mechanical properties of ceUs during entosis, we used an optical trap to measure the mechanical rigidity of live MCF7 ceils. We find that the MCAK cooperates with TIP150 to promote microtubule dynamics and modulate the mechanical rigidity of the cells during entosis. Our results show that a dynamic interaction of MCAK-TI P150 orchestrated by Aurora A-mediated phosphorylation governs entosis via regulating microtubule plus-end dynamics and cell rigidity. These data reveal a previously unknown mechanism of Aurora A regulation in the control of microtubule plasticity during ceU-in-ceU pro- cesses.     

吸胀番茄种子中β—微管蛋白的合成与DNA的复制

用免疫检测技术分析了吸胀的番茄种子胚根尖细胞中的β－微管蛋白，并用流体细胞分析仪分析了其细胞核ＤＮＡ的表现形式，发现种子在吸水８￣１６ｈ时，即可测得β－微管蛋白的标记，吸水４８ｈ标记密度达到高峰。     

组织预应力和Rho信号与肌原纤维细胞分化的关系

肌原纤维细胞(myofibroblast)在愈伤反应(wound-healing response)中扮演十分重要角色.而当机体组织受损时,组织内预应力环境将被破坏,出现不同程度的应力集中和应力松弛,从而影响细胞骨架张力,而骨架张力可以转化为细胞信号事件,针对组织预应力和Rho信号与肌原纤维细胞分化之间的关系进行探讨.     

The octarepeat region of hamster PrP （PrP51-91） enhances the formation of microtubule and antagonize Cu^2＋-induced microtubule-disrupting activity

Prion protein （PrP） is considered to associate with microtubule and its major component, tubulin. In the present study, octarepeat region of PrP （PrP51-91） was expressed in prokaryotic-expressing system. Using GST pull-down assay and co-immunoprecipitation, the molecular interaction between PrP51-91 and tubulin was observed. Our data also demonstrated that PrP51-91 could efficiently stimulate microtubule assembly in vitro, indicating a potential effect of PrP on microtubule dynamics. Moreover, PrP51-91 was confirmed to be able to antagonize Cu^2＋-induced microtubule-disrupting activity in vivo, partially protecting against Cu^2＋- intoxication to culture cells and stabilize cellular microtubule structure. The association of the octarepeat region of PrP with tubufin may further provide insight into the biological function of PrP in the neurons.