The proteome reveals serine/threonine kinase in pollen tube regulates S-RNase enzyme protein degradation in almond

ABSTRACT: Gametophytic self-incompatibility is the primary cause of low fruit set in almond. The mechanism of recognition that determines whether the gametophyte is successfully fertilized between pollen tube SCF (F-box-SSK1-Cul1-Rbx1) protein and pistil S-RNase protein during fertilization is unclear. In this study, the pistils of two almond cultivars 'Wanfeng' and 'Nonpareil' were used as the experimental materials after selfing- and nonselfing/cross-pollination, and pistils from the stamen-removed flowers were used as controls. We used fluorescence microscopy to observe the development of pollen tubes after pollination and 4-dimensional label-free quantitation (4D-LFQ) to detect the protein expression profiles of 'Wanfeng' and 'Nonpareil' pistils and in controls. The results showed that it took 24-36 h for the development of the pollen tube to 1/3 of the pistil, and a total of 7684 differentially accumulated proteins (DAPs) were identified in the pistil after pollinating 36 h, of which 7022 were quantifiable. The up- and down-regulation of the 12 differential protein expressions identified by parallel reaction monitoring (PRM) was the same as that identified by 4D-LFQ, with an average fold-change difference of 14.34%, a maximum of 31.37% and a minimum of 3.68%. Bioinformatics analysis based on the function of the differential proteins, including classification, enrichment, and clustering, identified RNA polymerases (4 DAPs), autophagy (3 DAPs), oxidative phosphorylation (3 DAPs), and homologous recombination (2 DAPs) pathways associated with the self-incompatibility process. The interaction between the serine/threonine kinase (MARK2) protein E3 ubiquitin ligase and the microtubule protein component microtubule-associated protein tau (MAPT/ACT) was found using the STRING database, which demonstrated the involvement of the MARK2 protein in the reaction of pollen tube recognition the nonself- and the self-S-RNase protein. It provides a new way to reveal the mechanism by which almond pollen tubes recognize the self and nonself S-RNase enzyme protein.

INSTRUMENT(S): timsTOF Pro

ORGANISM(S): Prunus Dulcis

SUBMITTER: Yeting XU  

LAB HEAD: Yeting XU

PROVIDER: PXD029128 | Pride | 2022-02-10

REPOSITORIES: Pride