Sperm cells of seed plants have lost their motility and are transported by the vegetative pollen tube cell for fertilization, but the extent to which they regulate their own transportation is a long-standing debate. Here we show that Arabidopsis lacking two bHLH transcription factors produces pollen without sperm cells. This abnormal pollen mostly behaves like the wild type and demonstrates that sperm cells are dispensable for normal pollen tube development.
We thank F. Tang and Y. Hu (Peking University, China) for technical help in single-cell RNA extraction, library construction and RNA-seq analysis. We are grateful to T. Aoyama and T. Tsuge (Kyoto University, Japan) for suggestions on preparing the manuscript. This work is supported by National Natural Science Foundation of China (grant Nos. 31620103903, 31621001 and 31370344) and partially by the 111 project. The Qu laboratory is supported by the Peking-Tsinghua Joint Center for Life Sciences and the Dresselhaus lab by the Collaborative Research Center SFB924. The supplementary materials contain additional data.
Supplementary Figures 1-7, Supplementary Tables 1 and 2, Supplementary Methods, Supplementary References.