在进化时间尺度上,染色体-微管合的功能性可塑性
Sundar Ram Sankaranarayanan1, Satya Dev Polisetty1, Kuladeep Das1
1Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.
Life science alliance
|October 4, 2023
概括
在Dam1复合体Dad2的子单元中,有一个维护的签名序列 (DSS),对于微管结合至关重要. 它对细胞活力的重要性随着中间体的长度而下降,这表明它在真菌线粒分裂中的适应性.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 在真菌中,Dam1复合体对于真菌在线粒分裂期间的精确染色体分离至关重要.
- Dad2是Dam1复合体的一个关键子单元,与其功能有关.
- 体结构在各种真菌物种之间有很大的差异,从点体到区域体.
研究的目的:
- 为了研究Dam1复合体内保存的Dad2签名序列 (DSS) 的功能意义.
- 为了确定一个特定的氨酸残留物 (R126) 在DSS内与中心体结构有关的作用.
- 了解中心分子长度如何影响Dad2 DSS对线粒细胞进展的必要性.
主要方法:
- 氨基酸序列分析以确定 Dad2 中的保存区域.
- 局部定向的突变生成产生 Dad2 变种 (Dad2ΔDSS, Dad2R126A).
- 用微管 (MTs) 净化复合Dam1复合物和体外结合试验.
- 在Saccharomyces cerevisiae,Candida albicans和Cryptococcus neoformans中对突变菌株的功能分析,以评估生存能力和染色体生物定向.
主要成果:
- 在 Dad2.中发现了一种保存的 10 氨基酸 Dad2 签名序列 (DSS).
- 在DSS中的氨酸残留物 (R126) 对于Saccharomyces cerevisiae (点中心体) 的生命力至关重要,但在Candida albicans或Cryptococcus neoformans (区域中心体) 中没有.
- 缺少DSS或关键氨酸的突变Dam1复合体未能结合MT或形成环.
- 随着中心粒长度的增加,对保存的氨酸的要求下降.
结论:
- Dad2 DSS及其保存的氨酸对Dam1复合体的功能至关重要,特别是MT结合和环形成.
- Dad2氨酸残留的基本性与中心粒长度相反相关,突出了功能性适应.
- 提出了一个模型,其中区域性中间体通过增强基因-MT相互作用,可能通过增加基因蛋白功能来适应 Dad2 arginine 中的突变.
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