Genome-Wide Identification and Expression Analysis of Gene Family in Rapeseed () Reveals Their Critical Roles in Biotic and Abiotic Stress Responses

Non-specific lipid transfer proteins (nsLTPs) are small cysteine-rich basic proteins which play essential roles in plant growth, development and abiotic/biotic stress response. However, there is limited information about the gene () family in rapeseed (). In this study, 283 genes were identified in rapeseed, which were distributed randomly in 19 chromosomes of rapeseed. Phylogenetic analysis showed that BnLTP proteins were divided into seven groups. Exon/intron structure and MEME motifs both remained highly conserved in each BnLTP group. Segmental duplication and hybridization of rapeseed's two sub-genomes mainly contributed to the expansion of the gene family. Various potential -elements that respond to plant growth, development, biotic/abiotic stresses, and phytohormone signals existed in gene promoters. Transcriptome analysis showed that genes were expressed in various tissues/organs with different levels and were also involved in the response to heat, drought, NaCl, cold, IAA and ABA stresses, as well as the treatment of fungal pathogens ( and ). The qRT-PCR assay validated the results of RNA-seq expression analysis of two top -responsive genes, and . Moreover, batches of might be regulated by BnTT1 and BnbZIP67 to play roles in the development, metabolism or adaptability of the seed coat and embryo in rapeseed. This work provides an important basis for further functional study of the genes in rapeseed quality improvement and stress resistance.