Functional Analysis of M-Locus Protein Kinase Revealed a Novel Regulatory Mechanism of Self-Incompatibility in Brassica napus L

• Published in: International journal of molecular sciences 2019-07, Vol.20 (13), p.3303
• Main Authors: Chen, Fang, Yang, Yong, Li, Bing, Liu, Zhiquan, Khan, Fawad, Zhang, Tong, Zhou, Guilong, Tu, Jinxing, Shen, Jinxiong, Yi, Bin, Fu, Tingdong, Dai, Cheng, Ma, Chaozhi
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Base Sequence; Brassica napus - enzymology; Brassica napus - genetics; Brassica napus - physiology; Cloning; CRISPR; CRISPR-Cas Systems - genetics; Functional analysis; Gene Editing; Gene Expression Regulation, Plant; Gene frequency; Genes; Genomes; Haplotypes; Incompatibility; Kinases; Ligands; Mutation; Mutation - genetics; Organ Specificity - genetics; Phylogenetics; Phylogeny; Plant reproduction; Plants, Genetically Modified; Pollination; Protein Isoforms - chemistry; Protein Isoforms - genetics; Protein Isoforms - metabolism; Protein kinase; Protein Kinase C - chemistry; Protein Kinase C - genetics; Protein Kinase C - metabolism; Proteins; Rape plants; RNA Interference; RNA, Messenger - genetics; RNA, Messenger - metabolism; Roles; Self-incompatibility; Self-Incompatibility in Flowering Plants - physiology; Transcription; Transgenic plants
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20133303

Self-incompatibility (SI) is a widespread mechanism in angiosperms that prevents inbreeding by rejecting self-pollen. However, the regulation of the SI response in is not well understood. Here, we report that the M-locus protein kinase ( ) , the functional homolog of in , controls SI in . We identified four paralogue genes in , including , , , and . Two transcripts of , and , were generated by alternative splicing. Tissue expression pattern analysis demonstrated that , especially , is highly expressed in reproductive organs, particularly in stigmas. We subsequently created RNA-silencing lines and CRISPR/Cas9-induced quadruple mutants of in SI line S-70. Phenotypic analysis revealed that SI response is partially suppressed in RNA-silencing lines and is completely blocked in quadruple mutants. These results indicate the importance of in regulating the SI response of . We found that the expression of SI positive regulators S-locus receptor kinase ( ) and Arm-Repeat Containing 1 ( ) are suppressed in mutant, whereas the self-compatibility (SC) element Glyoxalase I ( ) maintained a high expression level. Overall, our findings reveal a new regulatory mechanism of in the SI of