Summer Research Fellowship Programme of India's Science Academies

Identification and Characterization of the Superoxide Dismutase Gene Family in Brassica rapa

Dr Asif Mohammad Iqbal

Sher-e-kashmir University of Agricultural Sciences and Technology of Kashmir

Dr Santosh Kumar Updhyay

Panjab University Chandigarh


Brassica rapa includes many important crops that are cultivated as vegetables, condiments, and oilseeds. It is a major oilseed crop of Jammu & Kashmir which is grown in rabi season and covers a major area (>80%). Among the various antioxidants, Superoxide dismutase plays an important role in preventing oxidation of biological molecules. Accordingly they can protect plant tissues from an elevated concentration of O2 . The present study was therefore undertaken with the objective to unravel the genome wide analysis of SOD genes in B. rapa. The results have revealed that on the basis of domain organization a total of 17 BrSOD genes were identified, which were classified into eight BrCu-ZnSOD and nine BrFe-MnSOD genes. The subcellular localization revealed that the BrCu-ZnSODs were mostly predicted as cytoplasmic, and Fe-MnSODs as chloroplastic and mitochondrial. On the basis of SOD chromosomal distribution, the maximum of three genes were located on A10 (BrCu-ZnSODs) and A01 (BrFe-MnSODs). Phylogenetic analysis indicated that Cu-ZnSODs and Fe-MnSODs of B. rapa were separated by high bootstrap values. The exon-intron structure and the motif composition of BrSOD were displayed accordingly to their subclasses. Moreover, many cis-elements that respond to different stresses were found in the promoters of seventeen BrSOD genes. The studies on expression profile based on RNA-Seq data at various developmental stages revealed that all the genes expressed in all tissues except for BrCu-ZnSOD3, which was not expressed in roots, but expressed other tissues, implies diverse role of SODs across diifernt tissues. This genome wide analysis has provided comprehensive information about BrSOD gene family in B. rapa which would assist in elucidating their exact functions and facilitate their potential applications in the genetic improvement.

Keywords: Genome-wide analysis, Superoxide dismutase, Expression, B. rapa

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