Genome-Wide Analysis of the DUF4228 Family in Soybean and Functional Identification of GmDUF4228–70 in Response to Drought and Salt Stresses

Abstract

Domain of unknown function 4228 (DUF4228) proteins are a class of proteins widely found in plants, playing an important role in response to abiotic stresses. However, studies on the DUF4228 family in soybean (Glycine max L.) are sparse. In this study, we identified a total of 81 DUF4228 genes in soybean genome, named systematically based on their chromosome distributions. Results showed that these genes were unevenly distributed on the 20 chromosomes of soybean. The predicted soybean DUF4228 proteins were identified in three groups (Groups I–III) based on a maximum likelihood phylogenetic tree. Genetic structure analysis showed that most of the GmDUF4228 genes contained no introns. Expression profiling showed that GmDUF4228 genes were widely expressed in different organs and tissues in soybean. RNA-seq data were used to characterize the expression profiles of GmDUF4228 genes under the treatments of drought and salt stresses, with nine genes showing significant up-regulation under both drought and salt stress further functionally verified by promoter (cis-acting elements) analysis and quantitative real-time PCR (qRT-PCR). Due to its upregulation under drought and salt stresses based on both RNA-seq and qRT-PCR analyses, GmDUF4228-70 was selected for further functional analysis in transgenic plants. Under drought stress, the degree of leaf curling and wilting of the GmDUF4228-70-overexpressing (GmDUF4228-70-OE) line was lower than that of the empty vector (EV) line. GmDUF4228-70-OE lines also showed increased proline content, relative water content (RWC), and chlorophyll content, and decreased contents of malondialdehyde (MDA), H2O2, and O2–. Under salt stress, the changes in phenotypic and physiological indicators of transgenic plants were the same as those under drought stress. In addition, overexpression of the GmDUF4228-70 gene promoted the expression of marker genes under both drought and salt stresses. Taken together, the results indicated that GmDUF4228 genes play important roles in response to abiotic stresses in soybean.

Comprehensive Profiling of Tubby-Like Proteins in Soybean and Roles of the GmTLP8 Gene in Abiotic Stress Responses

“…Proline (Pro), malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), and superoxide anion (O 2 – ) levels are important indicators of the effects of abiotic stresses on plant growth ( Leng et al, 2021 ). Proline is a protective agent against osmotic stress; MDA reflects the degree of lipid oxidative damage; H 2 O 2 and O 2 – play immune and signal transduction roles, although excessive accumulation may lead to cell membrane damage ( Du et al, 2018 ; Zhang et al, 2019 ).…”

Genome-Wide Analysis of the Soybean TIFY Family and Identification of GmTIFY10e and GmTIFY10g Response to Salt Stress

“…The TIFY protein sequences of Arabidopsis , rice, soybean, apple, and grape were compared using ClustalW in the MEGA-X software. The maximum likelihood (ML) method was used to construct a phylogenetic tree for analyzing the phylogenetic relationship between TIFYs ( Kumar et al, 2016 ; Leng et al, 2021 ). The bootstrap method was used with 1,000 replicates.…”

Molecular Tools and Their Applications in Developing Salt-Tolerant Soybean (Glycine max L.) Cultivars

“…Identifying GWAS-based genes controlling salt tolerance in soybean has been a prolonged approach. Previously, many GAWS were conducted to identify the major gene families and their role in salt tolerance in soybean; however, further studies will identify more genes and alleles for a detailed understanding of the genetic mechanism of this trait and strengthen our knowledge to improve breeding programs [ 84 ]. A GWAS was conducted to identify the major gene for soybean salt tolerance.…”

“…The expression profile of these genes was characterized by using RNA sequencing data under salt stress. These results showed that DUF4228-70 plays an important role in the response to soybean salt stress [ 84 ]. The CrRLK1L proteins have a key role in salt tolerance in soybean, but their function is not yet fully understood.…”