A non-defensin peptide NPA1 attracts pollen tube in <i>Arabidopsis</i>
Weiqi Wang, Jiang‐Guo Meng, Fei Yang, Yinjiao Xu, Shizhen Li, Hong‐Ju Li
Abstract
In angiosperms, female gametophyte secretes a range of attractants to entice the pollen tube for fertilization. In dicots, all the identified attractants are defensin-like cysteine-rich peptides (CRPs) family members, while monocots, like <italic>Zea mays</italic> in Gramineae utilize non-CRP-type Egg Apparatus 1-like peptides as pollen tube attractants. However, whether dicots have non-CRP attractants is still unclear. Here we characterize a non-defensin peptide attractant NON-DEFENSIN PEPTIDE ATTRACTANT 1 (NPA1) in <italic>Arabidopsis</italic>. NPA1 is transcriptionally regulated by MYB98 in synergid. Besides the conspecific pollen tube, AtNPA1 is also capable to attract pollen tubes of sister species <italic>A. lyrata</italic> and <italic>C. rubella,</italic> but not <italic>E. salsugineum</italic>. Furthermore, when NPA1 is introduced to complement <italic>myb98</italic>, it restores pollen tube attraction and fertility to a level comparable to the complementation with LUREs. Together, this study identifies a new type of peptide attractant in dicots and highlights the diversity of the attraction cues and signaling pathways.