Catalase (CAT) Gene Family in Rapeseed (Brassica napus L.): Genome-Wide Analysis, Identification, and Expression Pattern in Response to Multiple Hormones and Abiotic Stress Conditions.

Ali Raza,Wenlong Nie,Yan Lv,Wei Su,Muhammad Azhar Hussain,Xuekun Zhang,Sundas Saher Mehmood,Ang Gao,Xiling Zou

doi:10.3390/ijms22084281

Abstract

Catalase (CAT) is an antioxidant enzyme expressed by the CAT gene family and exists in almost all aerobic organisms. Environmental stresses induce the generation of reactive oxygen species (ROS) that eventually hinder plant growth and development. The CAT enzyme translates the hydrogen peroxide (H2O2) to water (H2O) and reduce the ROS levels to shelter the cells’ death. So far, the CAT gene family has not been reported in rapeseed (Brassica napus L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the CAT genes in the rapeseed genome. The current study identified 14 BnCAT genes in the rapeseed genome. Based on phylogenetic and synteny analysis, the BnCATs belong to four groups (Groups I–IV). A gene structure and conserved motif analysis showed that Group I, Group II, and Group IV possess almost the same intron/exon pattern, and an equal number of motifs, while Group III contains diverse structures and contain 15 motifs. By analyzing the cis-elements in the promoters, we identified five hormone-correlated responsive elements and four stress-related responsive elements. Further, six putative bna-miRNAs were also identified, targeting three genes (BnCAT4, BnCAT6, and BnCAT8). Gene ontology (GO) enrichment analysis showed that the BnCAT genes were largely related to cellular organelles, ROS response, stimulus response, stress response, and antioxidant enzymes. Almost 10 BnCAT genes showed higher expression levels in different tissues, i.e., root, leaf, stem, and silique. The expression analysis showed that BnCAT1–BnCAT3 and BnCAT11–BnCAT13 were significantly upregulated by cold, salinity, abscisic acid (ABA), and gibberellic acid (GA) treatment, but not by drought and methyl jasmonate (MeJA). Notably, most of the genes were upregulated by waterlogging stress, except BnCAT6, BnCAT9, and BnCAT10. Our results opened new windows for future investigations and provided insights into the CAT family genes in rapeseed.

Highlights

IntroductionNumerous environmental factors, including abiotic and biotic stresses, significantly limit plants’ growth and development [1]
Introduction conditions of the Creative CommonsNumerous environmental factors, including abiotic and biotic stresses, significantly limit plants’ growth and development [1]
Upholding a considerable amount of reactive oxygen species (ROS) is crucial for appropriate cellular ROS signaling, and this amount can be attained by maintaining the balance among ROS generation and scavenging [2,3]

Summary

Introduction

Numerous environmental factors, including abiotic and biotic stresses, significantly limit plants’ growth and development [1]. The plant modifies its homeostatic apparatus by producing a surplus level of reactive oxygen species (ROS). ROS, which consist of a superoxide anion, hydrogen peroxide, hydroxyl radical, and singlet oxygen, are produced as a lethal derivative of regular oxygen metabolism and serve as a signaling component in plant molecular biology [2,3]. Many investigations have discovered that ROS homeostasis is important for upholding normal cellular roles [2,3]. Upholding a considerable amount of ROS is crucial for appropriate cellular ROS signaling, and this amount can be attained by maintaining the balance among ROS generation and scavenging [2,3]

Methods

Results

Discussion

Conclusion