title: The role of Ca2+and Ca2+channels in the gametophytic self-incompatibility of Pyrus pyrifolia.
abstract: In S-RNase-based self-incompatibility, S-RNase was previously thought to function as a selective RNase that inhibits pollen whose S-haplotype matches that in the pistil. In this study, we showed that S-RNase has a distinct effect on the regulation of Ca2+-permeable channel activity in the apical pollen tube in Pyrus pyrifolia. While non-self S-RNase has no effect, self S-RNase decreases the activity of Ca2+channels and disrupts the Ca2+gradient at the tip of the growing pollen tube during the gametophytic self-incompatibility (GSI) response. Extracellular Ca2+influx was suppressed 5min after self S-RNase treatment, and self-pollen tube growth was reduced at 50min after self S-RNase treatment. In the self-incompatible response, the expression of Ca2+-related genes was inhibited before RNA degradation. Therefore, self S-RNase suppresses Ca2+influx prior to arresting pollen tube growth via RNA degradation.
authors.affiliation: College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang, Qingdao City 266109, Shandong Province, China. Electronic address: quhaiyong@126.com.
authors.forename: Hai-Yong
authors.initials: HY
authors.lastname: Qu
authors.affiliation: College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang, Qingdao City 266109, Shandong Province, China. Electronic address: zhangzan@hotmail.com.
authors.forename: Zan
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang, Qingdao City 266109, Shandong Province, China. Electronic address: 1032761467@qq.com.
authors.forename: Fenfen
authors.initials: F
authors.lastname: Wu
authors.affiliation: College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang, Qingdao City 266109, Shandong Province, China. Electronic address: wangyzh304@163.com.
authors.forename: Yongzhang
authors.initials: Y
authors.lastname: Wang
mesh_terms: D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism*; D053205:Pollen Tube / Q000378:metabolism*; D031989:Pyrus / Q000378:metabolism*; D012260:Ribonucleases / Q000378:metabolism; D060436:Self-Incompatibility in Flowering Plants
chemical_list: D015220:Calcium Channels; D012260:Ribonucleases; C022542:ribonuclease S; D002118:Calcium
keywords: Ca(2+) channel; Non/self S-RNase; Pollen tube; Self-incompatibility