Genome-wide Systematic Survey and Analysis of the RNA Helicase Gene Family and their Response to Abiotic Stress in Sweetpotato

Abstract

Abstract RNA helicase is a large family that plays a significant role in plant evolution and in the abiotic stress response. Sweetpotato is one of the majority essential foods in the world, and their yields are often contrived by environmental stresses. Previously, the RNA helicase gene family has not been described in sweetpotato, hence we went a comprehensive genome-wide examination of the sweetpotato RNA helicase family, containing chromosome distribution, promoter elements, and motif compositions. All of 300 RNA helicase genes were divided into three subfamilies, including IbDEAD, IbDEAH and IbDExDH, and they are unevenly scattered across 15 chromosomes of the sweetpotato. Furthermore, tandem replication and segmental replication events played a key role in the amplification of sweetpotato RNA helicase genes. The collinear relationship amidst sweetpotato RNA helicase genes and 8 other related homologous genes in plants was deeply explored, which supplied a reliable basis for studying the development of sweetpotato RNA helicase gene family. RNA-seq examination and qRT-PCR recognition showed that the expression of eight RNA helicase genes was significantly diverse under four abiotic stresses (cold, drought, heat, salt). At the same time, the expression of these RNA helicases in different tissues of the 10 sweetpotato varieties also differed significantly. The promoters of the RNA helicase genes contain a great deal of cis-acting elements related to temperature, hormone and light response. The results indicated that sweetpotato RNA helicase genes played a key role in development or the abiotic stress response.