Mutations of short tandem repeats explain abundant trait heritability in Arabidopsis.

Background: Short tandem repeat (STR) mutations are major drivers of genetic variation and deeply influence phenotypic diversity and evolution, they are often overlooked despite their significant effects.

Results: Here, we leverage mutation accumulation lines descended from Col-0 accession of Arabidopsis thaliana to assess the variation in the repeat length of STRs (STR mutation rate). We find that STR mutation rate far exceeds single nucleotide polymorphisms rates.

Dispersed components drive temperature sensing and response in plants.

Plants are highly sensitive to temperature, and climate change is predicted to have negative impacts on agricultural productivity. Warming temperatures, coupled with a growing population, present a substantial challenge for food security and motivate research to understand how plants sense and respond to changes in temperature. Here, we synthesize our current understanding of temperature sensing and response in plants.

Core biological principles and tools stemming from basic Arabidopsis research.

The model plant Arabidopsis thaliana has been a cornerstone of research in plant biology, contributing transformative insights into fundamental biological processes across eukaryotes. In this vignette, we explore the role of Arabidopsis in elucidating immune mechanisms, where plant studies have informed mammalian immunity and translational regulation. We discuss how Arabidopsis-driven advancements in pangenomics and repeat expansions have reshaped our understanding of genomic variability and its implications for diseases like Friedreich's ataxia.

Simple sequence repeats and their expansions: role in plant development, environmental response and adaptation.

Repetitive DNA is a feature of all organisms, ranging from archaea and plants to humans. DNA repeats can be seen both in coding and in noncoding regions of the genome. Due to the recurring nature of the sequences, simple DNA repeats tend to be more prone to errors during replication and repair, resulting in variability in their unit length.

Arabidopsis research in 2030: Translating the computable plant.

Plants are essential for human survival. Over the past three decades, work with the reference plant Arabidopsis thaliana has significantly advanced plant biology research. One key event was the sequencing of its genome 25 years ago, which fostered many subsequent research technologies and datasets.

Genome-Wide Association Study Elucidates the Genetic Architecture of Manganese Tolerance in Brassica napus.

Brassica napus (canola) is a significant contributor to the world's oil production and is cultivated across continents, yet acidic soils with aluminium (Al) and manganese (Mn) toxicities limit its production. The genetic determinants underlying natural variation for acidic soil tolerance in canola are unknown and need to be determined. Through genome-wide association analysis of 326 canola accessions, we identified three QTLs for tolerance to Mn toxicity on chromosomes A09, C03, and C09.

Warm temperature perceived at the vegetative stage affects progeny seed germination in natural accessions of Arabidopsis thaliana.

Temperatures perceived early in the life cycle of mother plants can affect the germination of the offspring seeds. In Arabidopsis thaliana, vernalisation-insensitive mutants showed altered germination response to elevated maternal temperature, hence revealing a strong genetic determinism. However, the genetic control of this maternal effect and its prevalence across natural populations remain unclear.

SUMO protease FUG1, histone reader AL3 and chromodomain protein LHP1 are integral to repeat expansion-induced gene silencing in Arabidopsis thaliana.

Epigenetic gene silencing induced by expanded repeats can cause diverse phenotypes ranging from severe growth defects in plants to genetic diseases such as Friedreich's ataxia in humans. The molecular mechanisms underlying repeat expansion-induced epigenetic silencing remain largely unknown. Using a plant model with a temperature-sensitive phenotype, we have previously shown that expanded repeats can induce small RNAs, which in turn can lead to epigenetic silencing through the RNA-dependent DNA methylation pathway.

25 Years of thermomorphogenesis research: milestones and perspectives.

In 1998, Bill Gray and colleagues showed that warm temperatures trigger arabidopsis hypocotyl elongation in an auxin-dependent manner. This laid the foundation for a vibrant research discipline. With several active members of the 'thermomorphogenesis' community, we here reflect on 25 years of elevated ambient temperature research and look to the future.

CRY2 interacts with CIS1 to regulate thermosensory flowering via FLM alternative splicing.

Cryptochromes (CRYs) are evolutionarily conserved photolyase-like photoreceptors found in almost all species, including mammals. CRYs regulate transcription by modulating the activity of several transcription factors, but whether and how they affect pre-mRNA processing are unknown. Photoperiod and temperature are closely associated seasonal cues that influence reproductive timing in plants.

Quantifying splice-site usage: a simple yet powerful approach to analyze splicing.

RNA splicing, and variations in this process referred to as alternative splicing, are critical aspects of gene regulation in eukaryotes. From environmental responses in plants to being a primary link between genetic variation and disease in humans, splicing differences confer extensive phenotypic changes across diverse organisms (1-3). Regulation of splicing occurs through differential selection of splice sites in a splicing reaction, which results in variation in the abundance of isoforms and/or splicing events.

Dynamic mRNP Remodeling in Response to Internal and External Stimuli.

Signal transduction and the regulation of gene expression are fundamental processes in every cell. RNA-binding proteins (RBPs) play a key role in the post-transcriptional modulation of gene expression in response to both internal and external stimuli. However, how signaling pathways regulate the assembly of RBPs with mRNAs remains largely unknown.

The integral spliceosomal component CWC15 is required for development in Arabidopsis.

Efficient mRNA splicing is a prerequisite for protein biosynthesis and the eukaryotic splicing machinery is evolutionarily conserved among species of various phyla. At its catalytic core resides the activated splicing complex Bact consisting of the three small nuclear ribonucleoprotein complexes (snRNPs) U2, U5 and U6 and the so-called NineTeen complex (NTC) which is important for spliceosomal activation. CWC15 is an integral part of the NTC in humans and it is associated with the NTC in other species.

HISTONE DEACETYLASE 9 stimulates auxin-dependent thermomorphogenesis in by mediating H2A.Z depletion.

Many plant species respond to unfavorable high ambient temperatures by adjusting their vegetative body plan to facilitate cooling. This process is known as thermomorphogenesis and is induced by the phytohormone auxin. Here, we demonstrate that the chromatin-modifying enzyme HISTONE DEACETYLASE 9 (HDA9) mediates thermomorphogenesis but does not interfere with hypocotyl elongation during shade avoidance.

GWAS hints at pleiotropic roles for FLOWERING LOCUS T in flowering time and yield-related traits in canola.

Background: Transition to flowering at the right time is critical for local adaptation and to maximize grain yield in crops. Canola is an important oilseed crop with extensive variation in flowering time among varieties. However, our understanding of underlying genes and their role in canola productivity is limited.

Genetic Interactions and Molecular Evolution of the Duplicated Genes and Help Arabidopsis Plants Adapt to Different Ambient Temperatures.

Understanding how plants adapt to ambient temperatures has become a major challenge prompted by global climate change. This has led to the identification of several genes regulating the thermal plasticity of plant growth and flowering time. However, the mechanisms accounting for the natural variation and evolution of such developmental plasticity remain mostly unknown.

Transposable elements drive rapid phenotypic variation in .

Rapid phenotypic changes in traits of adaptive significance are crucial for organisms to thrive in changing environments. How such phenotypic variation is achieved rapidly, despite limited genetic variation in species that experience a genetic bottleneck is unknown. , an annual and inbreeding forb (Brassicaceae), is a great system for studying this basic question.

Thermomorphogenesis.

When exposed to warmer, nonstressful average temperatures, some plant organs grow and develop at a faster rate without affecting their final dimensions. Other plant organs show specific changes in morphology or development in a response termed thermomorphogenesis. Selected coding and noncoding RNA, chromatin features, alternative splicing variants, and signaling proteins change their abundance, localization, and/or intrinsic activity to mediate thermomorphogenesis.

RNA-Dependent Epigenetic Silencing Directs Transcriptional Downregulation Caused by Intronic Repeat Expansions.

Transcriptional downregulation caused by intronic triplet repeat expansions underlies diseases such as Friedreich's ataxia. This downregulation of gene expression is coupled with epigenetic changes, but the underlying mechanisms are unknown. Here, we show that an intronic GAA/TTC triplet expansion within the IIL1 gene of Arabidopsis thaliana results in accumulation of 24-nt short interfering RNAs (siRNAs) and repressive histone marks at the IIL1 locus, which in turn causes its transcriptional downregulation and an associated phenotype.

POWERDRESS-mediated histone deacetylation is essential for thermomorphogenesis in Arabidopsis thaliana.

Ambient temperature affects plant growth and even minor changes can substantially impact crop yields. The underlying mechanisms of temperature perception and response are just beginning to emerge. Chromatin remodeling, via the eviction of the histone variant H2A.

A Polynucleotide Repeat Expansion Causing Temperature-Sensitivity Persists in Wild Irish Accessions of Arabidopsis thaliana.

Triplet repeat expansions underlie several human genetic diseases such as Huntington's disease and Friedreich's ataxia. Although such mutations are primarily known from humans, a triplet expansion associated genetic defect has also been reported at the IIL1 locus in the Bur-0 accession of the model plant Arabidopsis thaliana. The IIL1 triplet expansion is an example of cryptic genetic variation as its phenotypic effects are seen only under genetic or environmental perturbation, with high temperatures resulting in a growth defect.