Loss of galactose metabolizing enzyme uge1 gene results in changes of cell dynamics during mitosis in Schizosaccharomyces pombe
TAN Xiumei1,2，DING Xiang3，YUAN Rongmei4，BAI Xin1，PU Dihong1， YE Ziyu1， HOU Yiling1
(1.Key Laboratory of Southwest China Wildlife Resources Conservation， Ministry of Education， College of Life Science， China West Normal University， Nanchong 637009， Sichuan， China；2.Management Committee of Nanxi Economic Development Zone， Yibin 644100， Sichuan， China；3.College of Environmental Science and Engineering， China West Normal University， Nanchong 637009， Sichuan， China；4.Sichuan Center for Disease Control and Prevention， Chengdu 610044， China)
Abstract：The uge1 gene encodes an enzyme involved in galactose metabolism， which plays an important role in cell growth and sexual reproduction. In this study， Schizosaccharomyces pombe was used as a system to analyze the effects of uge1 gene deletion on the dynamics of chromosomes， spindles and actin during mitosis by laser confocal imaging for the first time. Observations on interphase microtubules showed that the percentage of 5 microtubules in uge1Δ cells increased compared to wild type cells. Deletion of uge1 gene led to abnormal chromosome segregation， and both the frequency of monopolar spindle and the time between formation and depolymerization for spindle increased significantly. Deletion of uge1 gene also affected the elongation of spindle in mitotic prophase and anaphase. Examination on the type of spindle formation indicated that the frequency of “bar-shaped” spindle in uge1Δ cells was significantly reduced， and the “dot-shaped” spindle was significantly increased. Observations on the cell morphology suggested that both the length and ratio of length-width of uge1Δ cells increased. Besides， the length， the time from polymerization to depolymerization， the residence time and shrinkage time of actin bundles in uge1Δ cells increased significantly， while the rate of actin depolymerization in uge1Δ cells reduced significantly. These results indicated that the deletion of uge1 gene would lead to a variety of defects of mitotic chromosome， spindle and actin dynamics.
2023, Vol. 57 
