Search Results (4)

SIMILAR TO RCD-ONE (SRO) family members and transcription factors (TFs) often improve plant antioxidant capacity through interaction and co-regulation and participate in plant resistance to drought and high-salt stress. However, whether SROs are involved in the response to heavy metal stress, especially SRO genes with a specific response and tolerance characteristics to cadmium (Cd) stress, remains unclear. We first identified six SRO genes in the potato genome by PARP and RST domains. Special and conserved StSROs were found, and the spatio temporal tissue-specific expression patterns and co-expression network diagrams of StSROs under the stress of 5 heavy metals were constructed. Second, we identified StSRO6 as a major effector gene (StSRO6-MEG) and StSRO5 as a secondary effector gene (StSRO5-SEG) through a comprehensive analysis. Interestingly, they may hold true for various physiological or stress responses in plants. In addition, using systematic genomics and comparative omics techniques, the key gene StSRO6 that affects the difference in Cd accumulation was discovered, cloned in the low-Cd accumulation “Yunshu 505”, and transformed into the yeast mutant ycf1 for overexpression. The results proved that StSRO6 could confer Cd tolerance. Finally, through transient expression and in vitro culture tests, we hypothesized that StSROs 5/6 are regulated by the transcription factor StWRKY6 and mediates the reactive oxygen species (ROS) system to confer Cd tolerance. These findings offer a new perspective for understanding the mechanisms underlying Cd tolerance in plants, and simultaneously provide clues for the development of biological agents for preventing and controlling Cd migration and transformation. Full article

SIMILAR TO RCD-ONE (SRO) is a plant-specific small protein family that controls many biological processes including physiological development and stress responses. The SRO gene family has been studied in several plant species, but no detailed characterization and expression profiles of this important gene family were performed in cucumber. In this study, we characterize the SRO genes in cucumber, and determined their transcript levels in various tissues and under exposure to diverse biotic and abiotic stressors. Four SRO genes (named as CsSRO1–CsSRO4) were identified and isolated, which were distributed on three different chromosomes. Gene duplication analysis showed that only one pair of segmental duplication event was identified, but no tandem duplication events were detected. All CsSROs consist of the PARP domain and a C-terminal RST domain, while the N-terminal WWE domain was only present in CsSRO2 and CsSRO4. SROs from 15 plant species are divided into two groups (I and II), and group I can be further divided into four subgroups (Ia to Id) according to the phylogenetic tree. The conserved motif and gene structure analyses showed that SROs within the same branch of the phylogenetic tree have analogous conserved motifs configuration and gene structures. However, SRO genes possessed variable numbers of introns in different subgroups, which may affect the evolution of new family members. RNA-Seq data and qRT-PCR results showed that the four CsSRO genes have distinct expression pattern in various tissues and under diverse stresses, suggesting their multiple functions in plant growth and stress responses. The findings provide a basis for further research aiming at functional characterization of the regulatory mechanism to reveal the roles of CsSRO genes in developmental and stress-related processes of cucumber. Full article

SIMILAR TO RCD-ONEs (SROs) comprise a small plant-specific gene family which play important roles in regulating numerous growth and developmental processes and responses to environmental stresses. However, knowledge of SROs in sesame (Sesamum indicum L.) is limited. In this study, four SRO genes were identified in the sesame genome. Phylogenetic analysis showed that 64 SROs from 10 plant species were divided into two groups (Group I and II). Transcriptome data revealed different expression patterns of SiSROs over various tissues. Expression analysis showed that Group II SROs, especially SiSRO2b, exhibited a stronger response to various abiotic stresses and phytohormones than those in Group I, implying their crucial roles in response to environmental stimulus and hormone signals. In addition, the co-expression network and protein-protein interaction network indicated that SiSROs are associated with a wide range of stress responses. Moreover, transgenic yeast harboring SiSRO2b showed improved tolerance to salt, osmotic and oxidative stress, indicating SiSRO2b could confer multiple tolerances to transgenic yeast. Taken together, this study not only lays a foundation for further functional dissection of the SiSRO gene family, but also provides valuable gene candidates for genetic improvement of abiotic stress tolerance in sesame. Full article

Ipomoea cairica is a tropical plant and a wild relative of the food plant sweet potato (Ipomoea batatas), listed as one of the most invasive alien species in China. Recently, it has been reported that I. cairica had successfully invaded mangrove wetlands, indicating its high salt tolerance. Based on previous genetic studies, I. cairica offers a good model for characterizing stress-resistant genes. It has recently been identified that the SRO proteins (SIMILAR TO RCD-ONE) play important roles in a variety of stress and developmental responses. Radical-Induced Cell Death1 (RCD1) was the first identified plant SRO protein from Arabidopsis thaliana. As a typical SRO protein, IcSRO1 had a highly conservative WWE domain, a conserved PARP fold and protein C in the RST function area. The expression of IcSRO1 was induced by salt, drought, and the plant hormone ABA. The transgenic Arabidopsis overexpressing IcSRO1 showed higher tolerance against salt and drought stress along with lower accumulation of hydrogen peroxide (H₂O₂) and superoxide (O₂⁻) than the wild type. The IcSRO1 protein was localized in the nucleus after cultivation in the buffer. Our results indicated it could interact with Arabidopsis SALT OVERLY SENSITIVE 1 (AtSOS1), suggesting IcSRO1 may have similar functions. The pleiotropic effect of IcSRO1 on physiological processes contributes to the improvement of plant tolerance against diverse abiotic stresses, and may be associated with the adaptation of I. cairica to those environments with extreme saline and drought conditions. It therefore provides valuable gene resources for crop breeding enhancement. Full article