Genome-wide analyses of the Tubby-like proteins in Brassica napus  revealed their potential roles in the abiotic stress response

Abstract

Rapeseed (Brassica napus) is the third-largest source of edible vegetable oil in the world. One of the most crucial techniques to increase rapeseed oil production is to develop and utilize saline-alkali soil. Rapeseed biochemical underpinnings for tolerance to abiotic stress, particularly salt stress, are not entirely established. The tubby-like protein(TLP) gene family is a class of transcription factors originally discovered in obese mice. It plays several roles in the growth and development of plants, particularly in responseto biotic and abiotic stresses. Twenty-nine BnaTLPs members were identified in the B. napus cultivar Zhongshuang 11, which were unevenly distributed on 16 chromosomes of B. napus. Phylogenetic analysis showed that TLPproteins were separated into six groups based on protein homology in 9 plant species. Gene structure analysis showed that the majority of the BnaTLPs members have similar intron/exon and motif structures. Conserved domain analysis showed that BnaTLP8A, BnaTLP8C, and AtTLP8 lacked the N-terminal F-box protein, which may have an impact on how well they function. Collinearity analysis revealed that most BnaTLPsare the products of heterologous polyploidization and segmental duplication events. RNA-seq data showed that the majority of BnaTLPs members are expressed in significant tissues and organs at various developmental stages. Real-time qPCR results showed that BnaTLP9A, BnaTLP3C, BnaTLP2C, and BnaTLP10C.2 are upregulated in response to drought and salt stress in B. napus, while BnaTLP8A is downregulated. This study provides new insight into how TLPs react to drought and salt stresses, in addition to identifying candidate genes for abiotic stress improvement in B. napus.