《植物生理学报》 2016, 52(6): 877-885

拟南芥CDM1基因在减数分裂染色体浓缩过程中起重要作用

龙海飞, 张智敏, 陆平利^*

复旦大学生命科学学院, 植物科学研究所, 上海200438

通信作者：陆平利；E-mail: pinglilu@fudan.edu.cn

摘　要：

减数分裂是高等生物有性生殖中的一个重要环节, 其精确调控的染色体相互作用和动态变化是形成功能配子所必需的。前期的研究表明, CDM1在拟南芥小孢子形成中起重要作用, 但还不清楚它是否也参与减数分裂。本研究利用DAPI染色和着丝粒探针荧光标记原位杂交(FISH)比较分析了野生型和cdm1突变体减数分裂过程中染色体的动态变化。结果显示, 与野生型相比, cdm1同源染色体配对不受影响, 但在减数分裂II时期, cdm1染色体的浓缩程度出现一定程度的异常, 不能形成与野生型中相同的染色体结构。此外, qRT-PCR分析显示, 减数分裂相关基因MS5、MMD1、AML2、AtZIP4和AtMSH4在cdm1 4~7期(减数分裂时期)花药中的表达显著降低。因此推测, CDM1可能是通过影响与减数分裂相关基因的表达参与调控拟南芥减数分裂中的染色体浓缩和去浓缩过程。

关键词：拟南芥; 减数分裂; CDM1; FISH; 染色体浓缩

收稿：2016-03-23   修定：2016-05-05

资助：国家自然科学基金(31470280)。

The Arabidopsis CDM1 gene plays an important role in regulating meiotic chromosome condensation

LONG Hai-Fei, ZHANG Zhi-Min, LU Ping-Li^*

Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200438, China

Corresponding author: LU Ping-Li; E-mail: pinglilu@fudan.edu.cn

Abstract:

Meiosis is one of critical processes for sexual reproduction in eukaryotic organisms. During meiosis, functional gamete formation relies on accurate regulation of homologous chromosome interaction and dynamic movements. Previous study showed that the CDM1 gene is required for microspore development in Arabidopsis. However, so far, it is still unknown whether CDM1 is also involved in meiosis. In this study, meiotic chromosome spread with DAPI staining and centromere-probe labeled FISH were utilized to investigate meiotic chromosome dynamic movement in wild-type and cdm1 cells. The results showed that meiotic homologous chromosome paring in cdm1 is not affected. However, during meiosis II, chromosome condensation in cdm1 was detected abnormal, rarely forming similar chromosome structures as observed in wild-type. In addition, qRT-PCR analysis discovered that the expression of several meiosis-related genes, including MS5, MMD1, AML2, AtZIP4 and AtMSH4, was greatly decreased in cdm1 stage 4–7 anthers, in which meiosis undergoes, compared to that in wild type. In summary, we concluded that CDM1 may regulate meiotic chromosome condensation during meiosis II through influencing the expression of meiosis-related genes.

Key words: Arabidopsis; meiosis; CDM1; FISH; condensation