Responsive Alternative Splicing Events of Opisthopappus Species against Salt Stress

Abstract

Salt stress profoundly affects plant growth, prompting intricate molecular responses, such as alternative splicing (AS), for environmental adaptation. However, the response of AS events to salt stress in Opisthopappus (Opisthopappus taihangensis and Opisthopappus longilobus) remains unclear, which is a Taihang Mountain cliff-dwelling species. Using RNA-seq data, differentially expressed genes (DEGs) were identified under time and concentration gradients of salt stress. Two types of AS, skipped exon (SE) and mutually exclusive exons (MXE), were found. Differentially alternative splicing (DAS) genes in both species were significantly enriched in “protein phosphorylation”, “starch and sucrose metabolism”, and “plant hormone signal transduction” pathways. Meanwhile, distinct GO terms and KEGG pathways of DAS occurred between two species. Only a small subset of DAS genes overlapped with DEGs under salt stress. Although both species likely adopted protein phosphorylation to enhance salt stress tolerance, they exhibited distinct responses. The results indicated that the salt stress mechanisms of both Opisthopappus species exhibited similarities and differences in response to salt stress, which suggested that adaptive divergence might have occurred between them. This study initially provides a comprehensive description of salt responsive AS events in Opisthopappus and conveys some insights into the molecular mechanisms behind species tolerance on the Taihang Mountains.

The Genome-Wide Identification, Characterization, and Expression Profiles of the NADPH Oxidase (NOX) Gene Family under Drought and Salt Stress in Opisthopappus taihangensis (Asteraceae)

“…Between O. taihangensis and A. thaliana, homology analysis showed that OtNOX6 and OtNOX7 are one-to-one orthologous genes of AtNOX4 and AtNOX6, respectively (Table S7). In a previous study, we found that these two genes underwent exon-skipping under salt stress [36]. Studies have revealed that alternative splicing events frequently occur in response to external stimuli.…”

“…Thanks to the rapid development of sequencing technology, the sequencing of the highquality reference genome of O. taihangensis has been completed [35,36], allowing us to easily access the genes of interest at the whole-genome level. Thus, in this study, we identified all the members of NOXs and FROs in O. taihangensis for the first time.…”

Potential Response Patterns of Endogenous Hormones in Cliff Species Opisthopappus taihangensis and Opisthopappus longilobus under Salt Stress

“…Within Opisthopappus genus are two species ( Opisthopappus taihangensis ( O. taihangensis ) and Opisthopappus longilobus ( O. longilobus )). As a typical cliff plant both of these species exhibit good cold and drought resistance and are considered an important wild germplasm of Asteraceae [ 21 , 22 , 23 ].…”

RNA-seq analysis reveals transcriptome reprogramming and alternative splicing during early response to salt stress in tomato root

“…Previous studies have demonstrated that high salinity stress can promote the occurrence of alternative splicing of stress-responsive genes and affect the expression of the genes coding spliceosome components in Arabidopsis (Ding et al, 2014b;Feng et al, 2015;Gu et al, 2018), rice (Yu et al, 2021;Jian et al, 2022), wheat (Liu et al, 2018), Barley (Fu et al, 2019), Date Palm (Xu et al, 2021), grapevine (Jin et al, 2021), cotton (Zhu et al, 2018), Opisthopappus (Han et al, 2024), etc. However, the alternative splicing events in tomato root under salt stress remains to be resolved.…”