Relevance and Regulation of Alternative Splicing in Plant Heat Stress Response: Current Understanding and Future Directions

Abstract

Alternative splicing (AS) is a major mechanism for gene expression in eukaryotes, increasing proteome diversity but also regulating transcriptome abundance. High temperatures have a strong impact on the splicing profile of many genes and therefore AS is considered as an integral part of heat stress response. While many studies have established a detailed description of the diversity of the RNAome under heat stress in different plant species and stress regimes, little is known on the underlying mechanisms that control this temperature-sensitive process. AS is mainly regulated by the activity of splicing regulators. Changes in the abundance of these proteins through transcription and AS, post-translational modifications and interactions with exonic and intronic cis-elements and core elements of the spliceosomes modulate the outcome of pre-mRNA splicing. As a major part of pre-mRNAs are spliced co-transcriptionally, the chromatin environment along with the RNA polymerase II elongation play a major role in the regulation of pre-mRNA splicing under heat stress conditions. Despite its importance, our understanding on the regulation of heat stress sensitive AS in plants is scarce. In this review, we summarize the current status of knowledge on the regulation of AS in plants under heat stress conditions. We discuss possible implications of different pathways based on results from non-plant systems to provide a perspective for researchers who aim to elucidate the molecular basis of AS under high temperatures.

Integrated analysis of transcriptome and small RNAome reveals regulatory network of rapid and long-term response to heat stress in Rhododendron moulmainense

“…Exposure to heat stress induces hundreds of genes (Larkindale and Vierling 2008 ), signifying the necessary readjustment of molecular activities required for thermotolerance. AS is a prominent mechanism governing gene expression in eukaryotes, enhancing proteome diversity while also modulating transcriptome abundance (Rosenkranz et al 2022 ). AS is primarily controlled by splicing regulators, a large RNA–protein complex composed of five small nuclear RNAs (snRNAs: U1, U2, U4, U5, and U6) and hundreds of non-snRNP proteins (Reddy et al 2013 ; Staiger and Brown 2013 ).…”

Preparing for an uncertain future: molecular responses of plants facing climate change

“…Temperature-dependent alternative splicing may constitute a parallel mechanism. Sotirios Fragkostefanakis (University of Frankfurt) reported on general splicing regulators with a specific role in HS-dependent alternative splicing, thus illustrating a feedback loop to fine-tune HS response (Hu et al, 2020;Rosenkranz et al, 2022).…”

Unveiling unique alternative splicing responses to low temperature in Zoysia japonica through ZjRTD1.0, a high‐quality reference transcript dataset

“…Third, AS is closely linked to their ability to perceive and respond to various environmental stimuli. It has been shown that alternative splicing changes under different conditions, such as heat stress (Rosenkranz et al, 2022), cold acclimation (Calixto et al, 2018), or exposure to specific environmental cues (Martín et al, 2021). These splicing events can modulate gene expression and contribute to plant adaptation and survival in challenging environments.…”