Cysteine-rich peptides promote interspecific genetic isolation in Arabidopsis

• Published in: Science (American Association for the Advancement of Science) 2019-05, Vol.364 (6443), p.851-851
• Main Authors: Zhong, Sheng, Liu, Meiling, Wang, Zhijuan, Huang, Qingpei, Hou, Saiying, Xu, Yong-Chao, Ge, Zengxiang, Song, Zihan, Huang, Jiaying, Qiu, Xinyu, Shi, Yihao, Xiao, Junyu, Liu, Pei, Guo, Ya-Long, Dong, Juan, Dresselhaus, Thomas, Gu, Hongya, Qu, Li-Jia
• Format: Article
• Language: English
• Subjects: Acceleration; Accelerators; Animal reproduction; Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis Proteins - genetics; Arabidopsis Proteins - physiology; Attractants; Attraction; Biological evolution; Brassicaceae; Breeding success; Cysteine; Down-regulation; Emergence; Evolution; Fail safe systems; Fertility; Fertilization; Flowering; Flowers & plants; Gene expression; Gene Knockout Techniques; Gene regulation; Genes; Genes, Plant - physiology; Genetic isolation; Genomes; Historical metallurgy; Hybridization; Interspecific; Males; Molecular modelling; Mutants; Mutation; New species; Ovules; Peptides; Peptides - genetics; Peptides - physiology; Pistils; Plant reproduction; Plant reproductive structures; Plant species introduction; Plants (botany); Pollen; Pollen Tube - genetics; Pollen Tube - growth & development; Pollen tubes; Racing; Rainforests; Reproduction; Reproduction (biology); Reproductive Isolation; RESEARCH ARTICLE SUMMARY; Seed set; Septum; Signaling; Speciation; Tubes
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aau9564

Reproductive isolation is a prerequisite for speciation. Failure of communication between female tissues of the pistil and paternal pollen tubes imposes hybridization barriers in flowering plants. LURE1 (AtLURE1) peptides and their male receptor PRK6 aid attraction of the growing pollen tube to the ovule. Here, we report that the knockout of the entire gene family did not affect fertility, indicating that AtLURE1-PRK6-mediated signaling is not required for successful fertilization within one species. AtLURE1s instead function as pollen tube emergence accelerators that favor conspecific pollen over pollen from other species and thus promote reproductive isolation. We also identified maternal peptides XIUQIU1 to -4, which attract pollen tubes regardless of species. Cooperation between ovule attraction and pollen tube growth acceleration favors conspecific fertilization and promotes reproductive isolation.