ZmMTOPVIB Enables DNA Double-Strand Break Formation and Bipolar Spindle Assembly during Maize Meiosis  . Issue 4 (19th October 2020)

• Record Type: Journal Article
• Authors: Jing, Ju-Li; Zhang, Ting; Kao, Yu-Hsin; Huang, Tzu-Han; Wang, Chung-Ju Rachel; He, Yan
• Is Part Of: Plant physiology. Volume 184:Issue 4(2020)
• Page Start: 1811
• Page End: 1822
• Publication Date: 2020-10-19
• Subjects: Plant physiology -- Periodicals; Botany -- Periodicals; Periodicals; Electronic journals; 571.2
• DOI: 10.1104/pp.20.00933
• Languages: English
• ISSNs: 0032-0889

Abstract

Abstract : The dual roles of the topoisomerase-encoding MTOPVIB in meiotic double-strand break formation and bipolar spindle assembly and are evolutionarily conserved in monocot plants. Abstract: The meiotic TopoVI B subunit (MTopVIB) plays an essential role in double-strand break formation in mouse ( Mus musculus ), Arabidopsis ( Arabidopsis thaliana ), and rice ( Oryza sativa ), and recent work reveals that rice MTopVIB also plays an unexpected role in meiotic bipolar spindle assembly, highlighting multiple functions of MTopVIB during rice meiosis. In this work, we characterized the meiotic TopVIB in maize ( Zea mays ; ZmMTOPVIB ). The ZmmtopVIB mutant plants exhibited normal vegetative growth but male and female sterility. Meiotic double-strand break formation was abolished in mutant meiocytes. Despite normal assembly of axial elements, mutants showed severely affected synapsis and disrupted homologous pairing. Importantly, we showed that bipolar spindle assembly was also affected in ZmmtopVIB, resulting in triad and polyad formation. Overall, our results demonstrate that ZmMTOPVIB plays critical roles in double-strand break formation and homologous recombination. In addition, our results suggest that the function of MTOPVIB in bipolar spindle assembly is likely conserved across different monocots.