Transcriptome analyses reveals genes expression pattern of seed response to heat stress in Brassica napus L

Guizhen Gao, Jihong Hu, Xiaojun Zhang, Fugui Zhang, Mei Li, Xiaoming Wu
2021 Oil Crop Science  
Seeds may deteriorate and lose the ability to germinate stored under high temperature and humidity. Brassica napus is one of the most important oil crops. However, B.napus seeds were stored through the summer season with high ambient temperature, which lead to the loss of seed viability. In order to understand the mechanism of seed response to heat stress and improve seed heat tolerance, the B.napus seeds were treated with high temperature (40 ) and ultra-high temperature (60 ) for 4h. The
more » ... ) for 4h. The germination of heat-stressed seeds were obviously slow; the germination index and vigor index decreased with temperature increase from 40 to 60 , and 40 pretreatment could improve the tolerance of seeds to 60 heat stress. The transcriptomics results showed that 442 differentially expressed genes (DEGs) were identified in seeds after heat stress. Gene Ontology and KEGG pathway enrichment analysis revealed that some of the genes were involved in posttranslational modification, protein turnover, chaperones and carbohydrate transport, metabolic pathways and secondary metabolites biosynthesis pathway. Among these differentially expressed genes, sHSP and transcription factors genes J o u r n a l P r e -p r o o f were involved in heat stress tolerance. Thirty-two overlapping genes under different high temperature stress (40 and 60 ) were enriched in biological process of response to oxidative stress and response to abiotic stimulus. The expression trends of twelve genes randomly selected from the RNA-seq data were almost consistent with the results of qRT-PCR. Our results revealed several potential candidate genes and pathways related to heat responsive by high temperature,which is beneficial for further improving the heat tolerance characteristics in B.napus seeds . J o u r n a l P r e -p r o o f Transcriptome analyses reveals genes expression pattern of seed response to heat stress in Brassica napus L. Abstract: Seeds may deteriorate and lose the ability to germinate stored under high temperature and humidity. Brassica napus is one of the most important oil crops. However, B.napus seeds were stored through the summer season with high ambient temperature, which lead to the loss of seed viability. In order to understand the mechanism of seed response to heat stress and improve seed heat tolerance, the B.napus seeds were treated with high temperature (40 ) and ultra-high temperature (60 ) for 4h. The germination of heat-stressed seeds were obviously slow; the germination index and vigor index decreased with temperature increase from 40 to 60 , and 40 pretreatment could improve the tolerance of seeds to 60 heat stress. The transcriptomics results showed that 442 differentially expressed genes (DEGs) were identified in seeds after heat stress. Gene Ontology and KEGG pathway enrichment analysis revealed that some of the genes were involved in posttranslational modification, protein turnover, chaperones and carbohydrate transport, metabolic pathways and secondary metabolites biosynthesis pathway. Among these differentially expressed genes, sHSP and transcription factors genes J o u r n a l P r e -p r o o f were involved in heat stress tolerance. Thirty-two overlapping genes under different high temperature stress (40 and 60 ) were enriched in biological process of response to oxidative stress and response to abiotic stimulus. The expression trends of twelve genes randomly selected from the RNA-seq data were almost consistent with the results of qRT-PCR. Our results revealed several potential candidate genes and pathways related to heat responsive by high temperature,which is beneficial for further improving the heat tolerance characteristics in B.napus seeds . Germination percentage (%) is the total number of seed germination every day. Germination index (GI) and vigor index (VI) were evaluated at the end of the 7th day. GI = ∑ Gt Dt J o u r n a l P r e -p r o o f
doi:10.1016/j.ocsci.2021.04.005 fatcat:qd3gocpohfgirho7wtaeogp6ky