Ssu72磷酸酶缺失导致减数第二次分裂过程中纺锤体交叉

Ssu72 phosphatase deficiency leads to spindle crossing during the second meiotic division process

Ssu72磷酸酶是酵母裂解/多聚腺苷化因子(cleavage/polyadenylation factor,CPF)复合物的组成成分,可以催化RNA聚合酶II的C末端结构域(C-terminal domain,CTD)S5-P、S7-P的去磷酸化。后又有研究指出Ssu72磷酸酶参与有丝分裂过程中染色体凝聚力的调控。为进一步明确Ssu72磷酸酶是否会影响裂殖酵母减数分裂过程中染色体的分离,本研究利用绿色荧光蛋白(green fluorescent protein,GFP)标记着丝粒、红色荧光蛋白标记微管蛋白Atb2,并在荧光显微镜下实时观察ssu72Δ细胞的整个减数分裂染色体分离过程。结果表明,ssu72Δ细胞在减数第二次分裂中后期发生纺锤体交叉,并且这种纺锤体的交叉产生了一种新型的孢子排布缺陷模式。本研究为高等生物中磷酸酶Ssu72的研究提供重要的借鉴意义。

Ssu72 is a component of the yeast cleavage/polyadenylation factor(CPF)complex,which catalyzes the dephosphorylation of the C-terminal domain(CTD)of RNA polymerase II at S5-P and S7-P.It has been shown that Ssu72 phosphatase is involved in regulating chromosome cohesion during mitosis.To further clarify whether Ssu72 phosphatase affects chromosome separation during meiotic division in Schizosaccharomyces pombe,we utilized green fluorescent protein(GFP)to label centromeres and red fluorescent protein to label microtubule protein Atb2.The entire meiotic chromosome separation process of ssu72Δcells was observed in real-time under fluorescence microscope.It was found that two spindles of ssu72Δcells crossed during the metaphase and anaphase of the second meiotic division,and this spindle crossing led to a new type of spore defect distribution pattern.The results of this study can provide important reference significance for studying the roles of phosphatase Ssu72 in higher organisms.