ABA‐stimulated SoDOG1 expression is after‐ripening inhibited during early imbibition of germinating Sisymbrium officinale seeds

Abstract

DELAY OF GERMINATION 1 (AtDOG1) was the first gene identified as dormancy-associated, but its physiological role in germination is far from being understood. Here, an orthologue of AtDOG1 in Sisymbrium officinale (SoDOG1; KM009050) is being reported. Phylogenetically, the SoDOG1 gene is included into the dicotyledonous group together with DOG1 from Arabidopsis thaliana (EF028470), Brassica rapa (AC189537), Lepidium papillosum (JX512183, JX512185) and Lepidium sativum (GQ411192). The SoDOG1 expression peaked at the onset of the silique maturation stage and there was presence of SoDOG1-mRNA in the freshly collected viable dry seed (i.e. AR0). The SoDOG1 transcripts were also found in other organs, such as open and closed flowers and to a lesser degree in roots and stems. We have previously reported in S. officinale seeds in which sensu stricto germination is positively affected by nitrate and both testa and micropylar endosperm ruptures are temporally separated. In dry viable seeds, the SoDOG1-mRNA level in three different after-ripening (AR) status was AR0 ≈ AR7 (optimal AR) < AR27 (optimal AR was almost lost). The presence of nitrate in the AR0 seed imbibition medium markedly decreased the SoDOG1 expression during sensu stricto germination. However, the nitrate stimulated the SoDOG1 expression during imbibition of AR7 compared to AR0. At the early AR0 seed imbibition (3-6 h), exogenous ABA provoked a very strong stimulation of the SoDOG1 expression. AR inhibits ABA-induced SoDOG1 expression during early germination and gibberellins (GA) can partially mimic this AR effect. A view on the integration of all found results in the sensu stricto germination of S. officinale was conducted.

Whole genome-wide transcript profiling to identify differentially expressed genes associated with seed field emergence in two soybean low phytate mutants

“…Furthermore, reactive oxygen species production including the superoxide anion radical, hydrogen peroxide and the hydroxyl radical can cause oxidative damage to cellular components and reduce seeds ability to germination [26, 27]. Finally, plant hormones such as abscisic acid, gibberellins and ethylene play a very important role in seeds germination [28]. According to above researches and the DGEs numbers in functional categories, in this research, we were concerned with the functional categories of DEGs (regardless of regulation direction) related to seed germination process.…”

Delay of Germination-1 (DOG1): A Key to Understanding Seed Dormancy

“…Similarly, in cruciferae Sysimbrium officinale, ABA shows a positive effect on the SoDOG1 expression during early imbibition. Moreover, this positive effect may be inhibited by optimal AR whereas GAs can partly mimic the AR effect [7]. Experiments of chromatin immunoprecipitation (ChIP) showed no direct interaction of ABI3 with the promoter region of DOG1 [53].…”

“…In parallel to Arabidopsis, DOG1 genes have been found in other species of Brassicaceae [7,11,12] and some of Lactuca [13]. The amino acid sequences similarity among the studied dicot DOG1 is high [7,14]. Other authors have described DOGL genes in many monocot species, such as Hordeum vulgare, Triticum aestivum, Oryza sativum, Zea mays, Sorghum bicolor, and Brachypodium distachyon [5,14,15] (Figure 1, Figure S1, Table S1).…”

“…In both cases, there is a reduction of crop production [1,4,5]. PD is established and maintained in the viable dry seed, and throughout several molecular paths (e.g., after-ripening (AR) and exposure to gentle cooling) and can be broken gradually [6,7]. On the other hand, non-dormant seeds of various species have been reported to achieve secondary dormancy (SD) upon exposure to unfavorable conditions for germination [1].…”

“…DOGL1, DOGL2, and DOGL3 are relatively like DOG1, whereas DOGL4 and DOGL5 show only 28 and 30% similarity with DOG1 in amino acid sequence, respectively [1]. In parallel to Arabidopsis, DOG1 genes have been found in other species of Brassicaceae [7,11,12] and some of Lactuca [13]. The amino acid sequences similarity among the studied dicot DOG1 is high [7,14].…”