Genome-Wide Characterization and Identification of Trihelix Transcription Factor and Expression Profiling in Response to Abiotic Stresses in Rice (Oryza sativa L.)

Abstract

Trihelix transcription factors play a role in plant growth, development and various stress responses. Here, we identified 41 trihelix family genes in the rice genome. These OsMSLs (Myb/SANT-LIKE) were located on twelve chromosomes. Synteny analysis indicated only six duplicated gene pairs in the rice trihelix family. Phylogenetic analysis of these OsMSLs and the trihelix genes from other species divided them into five clusters. OsMSLs from different groups significantly diverged in terms of gene structure and conserved functional domains. However, all OsMSLs contained the same five cis-elements. Some of these were responsive to light and dehydration stress. All OsMSLs expressed in four tissues and six developmental stages of rice but with different expression patterns. Quantitative real-time PCR analysis revealed that the OsMSLs responded to abiotic stresses including drought and high salt stress and stress signal molecule including ABA (abscisic acid), hydrogen peroxide. OsMSL39 were simultaneously expressed under all treatments, while OsMSL28 showed high expression under hydrogen peroxide, drought, and high salt treatments. Moreover, OsMSL16/27/33 displayed significant expression under ABA and drought treatments. Nevertheless, their responses were regulated by light. The expression levels of the 12 chosen OsMSLs differed between light and dark conditions. In conclusion, our results helped elucidate the biological functions of rice trihelix genes and provided a theoretical basis for further characterizing their biological roles in responding to abiotic stresses.

Genome-Wide Identification and Expression Profiling Analysis of the Trihelix Gene Family Under Abiotic Stresses in Medicago truncatula

“…GT-2 and SH4 clades contained eight and six MtGT members, respectively. These results were similar to the genes distribution of different subgroups in Arabidopsis and rice [12,23].…”

“…Recently, a few more trihelix TFs have been characterized which played important roles in multiple processes during plant growth and development, such as trichome development [ 14 ], shattering of the mature seed during crop domestication [ 17 ], morphogenesis control of floral organs [ 13 ], and response to abiotic and biotic stresses [ 15 , 18 ]. In this study, we identified 38 MtGT genes in M. truncatula , which is similar to the number of trihelix genes in Arabidopsis (30) [ 12 ], rice (41) [ 23 ], and tomato (36) [ 24 ]. Additionally, it is close to the average number of trihelix genes on each subgenome of wheat (31) [ 29 ].…”

“…Particularly, its genome has a high similarity to that of alfalfa ( Medicago sativa ), the most widely cultivated economic forage plant in the world; hence, studies on M. truncatula can provide important genetic reference information for alfalfa. At present, trihelix genes have been systematically identified and analyzed in many plants, including Arabidopsis [ 12 ], Oryza sativa [ 23 ], Solanum lycopersicum [ 24 ], Brassica rapa [ 25 ], Gossypium arboreum [ 26 ], G. max [ 27 ], Chrysanthemum morifolium [ 28 ], Triticum aestivum [ 29 ] and Populus trichocarpa [ 30 ]. However, information and functional analysis of the trihelix family in M. truncatula has not yet been performed.…”

Identification and in Silico Characterization of GT Factors Involved in Phytohormone and Abiotic Stresses Responses in Brachypodium distachyon

“…Only six duplication events were found, and tandem duplications were found among three BdGT gene pairs, such as BdGT16 and BdGT24 , BdGT19 and BdGT26 , and BdGT20 and BdGT28 . The results suggest BdGT genes were less conserved, implying most genes might not originate from the same ancestor, which was consist with the report in rice [12]. Gene synteny analysis showed that almost all B. distachyon GT genes (except BdGT12 ) showed a syntenic relationship with those in rice, maize, and Arabidopsis , implying this family genes had a high degree of retention following whole-genome duplication (Figure 6).…”

“…The GT genes have been systematically studied in model plants such as Arabidopsis , tomato, soybean, chrysanthemum and rice. For instance, there are 30 members in Arabidopsis , 36 in tomato, 63 in soybean, 20 in chrysanthemum, and 41 in rice [5,10,11,12,13]. Generally, these family members contain a conserved DNA-binding domain, which has three tandem helices (helix-loop-helix-loop-helix) that combine specifically with the GT elements, a light-responsive DNA element [14].…”