Dissecting Pistil Responses to Incompatible and Compatible Pollen in Self-Incompatibility Brassica oleracea Using Comparative Proteomics

Abstract

Angiosperms have developed self-incompatibility (SI) systems to reject self-pollen, thereby promoting outcrossing. The Brassicaceae belongs to typical sporophytic system, having a single S-locus controlled SI response, and was chosen as a model system to study SI-related intercellular signal transduction. In this regard, the downstream factor of EXO70A1 was unknown. Here, protein two-dimensional electrophoresis (2-DE) method and coupled with matrix-assisted laser desorption ionization/time of flight of flight mass spectrometry (MALDI-TOF -MS) and peptide mass fingerprinting (PMF) was used to further explore the mechanism of SI responses in Brassica oleracea L. var. capitata L. at protein level. To further confirm the time point of protein profile change, total proteins were collected from B. oleracea pistils at 0 min, 1 h, and 2 h after self-pollination. In total 902, 1088 and 1023 protein spots were separated in 0 min, 1 h and 2 h 2-DE maps, respectively. Our analyses of self-pollination profiles indicated that proteins mainly changed at 1 h post-pollination in B. oleracea. Moreover, 1077 protein spots were separated in cross-pollinated 1 h (CP) pistil 2-DE map. MALDI-TOF-MS and PMF successfully identified 34 differentially-expressed proteins (DEPs) in SP and CP 1 h 2-DE maps. Gene ontology and KEGG analysis revealed an array of proteins grouped in the following categories: stress and defense response (35%), protein metabolism (18%), carbohydrate and energy metabolism (12%), regulation of translation (9%), pollen tube development (12%), transport (9%) and cytoskeletal (6%). Sets of DEPs identified specifically in SP or only up-regulated expressed in CP pistils were chosen for funther investigating in floral organs and during the process of self- and cross-pollination. The function of these DEPs in terms of their potential involvement in SI in B. oleracea is discussed.

Acta Biologica Cracoviensia s. Botanica

“…a b that the interaction between SRK7 kinase domain and CaM12 depended on its four EF-hand domains (Xu et al, 2013). Proteomics analysis revealed that the protein profile in the pistil changed after either compatible or incompatible pollination at 1 h (Chen et al, 2013;Zeng et al, 2017). In GST pull down assay, we separated one specific band located between 130-180 kDa size in the pistil proteins + GST-CML27 lane.…”

“…A number of molecular components in the selfincompatibility signaling pathway have been identified in both pollen and the pistil organs (Stone et al, 2003;Takasaki et al, 2000;). For further investigated potential candidate genes involved in self-incompatibility, RNA-sequence and proteomics were explored to study pistil molecules in the pollination process (Samuel et al, 2011;Zhang et al, 2015;Zeng et al, 2017). The mRNA levels of key regulatory components in the selfincompatibility signaling pathway, including the levels in SRK and ARC1 have been shown to increase during the initial 30 min, followed by a reduction at 1 h after pollination .…”

Genome-Wide Identification of the U-Box E3 Ubiquitin Ligase Gene Family in Cabbage (Brassica oleracea var. capitata) and Its Expression Analysis in Response to Cold Stress and Pathogen Infection

“…Moreover, Brassica oleracea is also considered to be a model for the study of the genomic evolution of Brassica species due to its typical diploid genome structure [ 26 ]. The molecular mechanisms underlying many significant biological processes, including pigment accumulation [ 27 ], self-incompatibility [ 28 ], and flowering [ 29 ], have been dissected in Brassica oleracea , while a lot of classic biotechnologies, including virus-induced gene silencing (VIGS) [ 30 ] and CRISPR/Cas9-based gene editing [ 31 ], have also been applied in Brassica oleracea . Thus, the discovery of functional genes in Brassica oleracea is required for the genetic improvement of desired traits by the most advanced molecular breeding strategies.…”