Genome-Wide Identification and Analysis of the Ascorbate Peroxidase (APX) Gene Family of Winter Rapeseed (Brassica rapa L.) Under Abiotic Stress

Abstract

Winter Brassica rapa (B. rapa) is an important oilseed crop in northern China, but the mechanism of its cold resistance remains unclear. Ascorbate peroxidase (APX) plays important roles in the response of this plant to abiotic stress and in scavenging free radicals. In this study, the roles of APX proteins in the cold response and superoxide metabolism pathways in rapeseed species were investigated, and a comprehensive analysis of phylogeny, chromosome distribution, motif identification, sequence structure, gene duplication, and RNA-seq expression profiles in the APX gene family was conducted. Most BrAPX genes were specifically expressed under cold stress and behaved significantly differently in cold-tolerant and weakly cold-resistant varieties. Quantitative real-time-PCR (qRT-PCR) was also used to verify the differences in expression between these two varieties under cold, freezing, drought and heat stress. The expression of five BrAPX genes was significantly upregulated in growth cones at 3 h of cold stress, while their expression was significantly lower at 24 h than at 3 h. The expression of Bra015403 and Bra003918 was significantly higher in “Longyou-7” growth cones than in other treatments. Five BrAPXs (Bra035235, Bra003918, Bra033040, Bra017120, and Bra031934) were closely associated with abiotic stress responses in B. rapa. These candidate genes may play important roles in the response of B. rapa to low temperature stress and provide new information for the elucidation of the cold resistance mechanism in B. rapa.

Studying Salt-Induced Shifts in Gene Expression Patterns of Glucosinolate Transporters and Glucosinolate Accumulation in Two Contrasting Brassica Species

“…Genome-wide studies of various gene families in Brassicaceae have consistently indicated their expansion compared with Arabidopsis. Notable examples are not limited to but include APX, NPR, DOF, shattering genes, SOD, and PEBP [68][69][70][71][72][73]. Regarding amphidiploids, the presence of twelve genes suggests these species inherited six genes from each of their parental species, corresponding to the GTR genes found in Arabidopsis [42].…”

Genome-Wide Identification of GSTs Gene Family and Functional Analysis of BraGSTF2 of Winter Rapeseed (Brassica rapa L.) under Cold Stress

“…The positive clones were selected to interact with LR Clonase enzyme (Invitrogen, Carlsbad, CA, USA) to connect to the overexpression vector pEarly-Gate101, following the instructions for Agrobacterium tumefaciens GV3101 (Anyu Biotechnology Co., Ltd., Shanghai, China). After the bacteria were picked out from the coated plate, colony PCR was carried out, and the positive bacterial solution was selected and preserved [ 43 ].…”

Genome-wide identification and analysis of ascorbate peroxidase (APX) gene family in hemp (Cannabis sativa L.) under various abiotic stresses

“…To date, the APX gene has been identified in many plants. Examples include pepper ( Capsicum annuum L.) ( Pang et al, 2023 ), tomato ( Solanum lycopersicum L.) ( Hu et al, 2021 ), upland cotton ( Gossypium hirsutum L.), winter rapeseed ( Brassica rapa L.) ( Ma et al, 2022 ), Arabidopsis thaliana ( Kameoka et al, 2021 ), and sorghum ( Sorghum bicolor L.) ( Akbudak et al, 2018 ). Additionally, various APX members have been recognized for their roles in abiotic stress responses.…”