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In flowering plants, the altating life cycle between diploid sporophyte and haploid gametophyte generations is completed through the synergistic action of sporophyte and gametophyte. The formation of viable pollen grains in anther cavity is the key to the process (Scott et al, 2004; Ma, 2005; Wilson and Zhang, 2009). The four-layer anther wall has specific functions and coordination in the whole process, and plays an important role in the formation of pollen grains (Walbot and Egger, 2016). During the pollen maturity stage, the middle layer and the tapetum undergo programmed degeneration (Scott et al, 2004). The tapetum which is the innermost layer of anther wall directly contacts with the developing microspores (Parish and Li, 2010). Tapetal cells may support nutrients and other chemicals including sporopollenin precursors for the normal development of pollen wall. In rice, multiple genes play essential roles in the process of the anther layers’ degeneration, including MULTIPLE SPOROCYTE1 (MSP1), UNDEVELOPED TAPETUM (UDT1), tapetum degeneration retardation (TDR ), TDR-interacting protein 2 (TIP2, bHLH142), the myeloblastosis (MYB) transcription factor GAMYB, plant homeodomain (PHD)-finger protein persistent tapetal cell 1 (PTC1) and TGACG MOTIF-BINDING FACTOR (TGA) transcription factor OsTGA10 (Zhao et al, 2002; Nonomura et al, 2003; Jung et al, 2005; Li et al, 2006; Aya et al, 2009; Fu et al, 2014; Ko et al, 2014; Ranjan et al, 2017; Chen et al, 2018; Du et al, 2019). Therefore, it is important to obtain pollen sterile mutants controlled by new genes or multiple alleles for studying the mechanism of male sterility.