Scientists Discover a Turning Point for the Mitosis to Meiosis Transition.  

　　On 29th November, Plant Physiology online published a research paper entitled “Stage-specific gene profiling of germinal cells helps delineate the mitosis/meiosis transition” from Prof. Weihua Tang’s group at Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Science (CAS). This study reveals the transcriptome dynamics of germinal cells undergoing the mitosis-meiosis switch and pinpoints crucial turning points for this transition.  

　　Sexual reproduction is the predominant reproduction style in nature. The most pivotal event of sexual reproduction is the transition from mitotic to meiotic cell cycle. In plants, committed germinal cells undergo several rounds of mitotic proliferation before entering meiosis. However, the mechanisms orchestrating meiosis initiation in germinal initial cells remain elusive.  

　　Based on the precise analysis of germinal cell stage in developing maize anthers, Dr. Tang and her colleagues obtained germinal cells at three sequential stages, i.e. archesporial cells (AR) undergoing the last phase of mitotic proliferation, enlarging pollen mother cell (ePMC) at interphase and pollen mother cell just starting meiosis, using laser capture microdissection, and performed microarray analysis. The expression features of key meiosis genes, transcription factor subsets and E3 ubiquitin ligases in germinal cells indicate that the ePMC stage is a critical turning point for the mitosis-to-meiosis transition. Mass spectrometry result further suggests that many meiotic genes are not only transcribed but also translated before meiosis. This study identified more candidate meiosis-specific genes and pathways enriched in the mitosis/meiosis transition. Therefore, this study provides more leads for scientific hypotheses for testing, and helps delineate the molecular basis for the mitosis/meiosis transition.  

　　This research was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences, the National Key Research and Development Program of China (2016YFD0100600), the National GMO project (2016ZX08009-003), and the Natural Science Foundation of China (Grant 31570318).  

　　Article website:   

　　http://www.plantphysiology.org/content/early/2017/11/29/pp.17.01483  

　　CONTACT:  

　　Dr. Weihua Tang, PhD, Professor  

　　National Key Laboratory of Plant Molecular Genetics  

　　CAS Center for Excellence in Molecular Plant Sciences  

　　Institute of Plant Physiology and Ecology (SIPPE)  

　　Chinese Academy of science (CAS)  

　　+86-21-54924072  

　　Email: whtang@sibs.ac.cn  

　　Laser microdissection and gene profiling of maize germinal cells before, at and after mitosis-to-meiosis transition