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bioRxiv2025

The potential to breed for genetic legacy effects in sustainable farming systems

Legume crops provide protein-rich food, critical disease breaks in cereal rotations, and contribute to soil fertility through symbiotic nitrogen fixation. However, crop improvement programs typically focus on within-crop performance rather than system-level benefits. We hypothesise that legacy effects (the influence of one crops genotype on subsequent crop performance) are under genetic control and could be leveraged in breeding programs. To test this, we evaluated how 309 genetically diverse mungbean genotypes influence subsequent wheat performance. The mungbean panel was grown, followed by a single wheat cultivar sown in the same plot locations. Remarkably, wheat yield varied by nearly 1 t ha{square}{superscript 1} (2.52-3.49 t ha{square}{superscript 1}) depending solely on the preceding mungbean genotype, with legacy traits displaying moderate heritability (H{superscript 2}: 0.43-0.65), demonstrating untapped genetic potential for breeding. Analyses of mungbean traits, soil properties, and volatile organic compounds implicated root architecture, symbiotic nitrogen fixation and soil microbiome as potential biological drivers of legacy effects. Haplotype mapping identified genomic regions in mungbean associated with wheat yield and protein, revealing trade-offs between within-crop and legacy performance. Genetic simulations using empirically derived marker effects compared genomic selection strategies targeting mungbean yield, wheat yield, or both simultaneously. Balanced selection (50:50 weighting) achieved simultaneous gains in both crops (19.5% and 7.6%), highlighting the opportunity to breed for system-level productivity with reduced input requirements.

plant biology↗

bioRxiv2023

Evidence that variation in root anatomy contributes to local adaptation in Mexican native maize

Mexican native maize (Zea mays ssp. mays) is adapted to a wide range of climatic and edaphic conditions. Here, we focus specifically on the potential role of root anatomical variation in this adaptation. In light of the investment required to characterize root anatomy, we present a machine learning approach using environmental descriptors to project trait variation from a relatively small training panel onto a larger panel of genotyped and georeferenced Mexican maize accessions. The resulting models defined potential biologically relevant clines across a complex environment and were used subsequently in genotype-environment association. We found evidence of systematic variation in maize root anatomy across Mexico, notably a prevalence of trait combinations favoring a reduction in axial conductance in cooler, drier highland areas. We discuss our results in the context of previously described water-banking strategies and present candidate genes that are associated with both root anatomical and environmental variation. Our strategy is a refinement of standard environmental genome wide association analysis that is applicable whenever a training set of georeferenced phenotypic data is available.

plant biology↗

bioRxiv2024

An expedited qualitative profiling of free amino acids in plant tissues using liquid chromatography-mass spectrometry (LC-MS) in conjunction with MS-DIAL

The estimation of relative levels of amino acids is crucial for understanding various biological processes in plants, including photosynthesis, stress tolerance, and the uptake and translocation of nutrients. A wide range of liquid chromatography (LC; HPLC/UHPLC) -based methods is available for measuring the quantity of amino acids in plants. Additionally, the coupling of LC with mass spectrometry (MS) significantly enhanced the robustness of existing chromatographic methods used for amino acid quantification. However, accurate annotation and integration of mass peaks can be challenging for plant biologists with limited experience in analyzing MS data, especially in studies involving large datasets with multiple treatments and/or replicates. Further, there are instances when the experiment demands an overall view of the amino acids profile rather than focusing on absolute quantification. The present protocol provides a detailed LC-MS method for obtaining a qualitative amino acids profile using MS-DIAL, a versatile and user-friendly program for processing MS data. Free amino acids were extracted from the leaves of control and Tomato leaf curl Palampur virus (ToLCPalV)-infected Nicotiana benthamiana plants. Extracted amino acids were derivatized and separated using UHPLC-QTOF, with each amino acid subsequently identified by aligning mass data with a custom text library created in MS-DIAL. Further, MS-DIAL was employed for internal standard-based normalization to obtain a qualitative profile of 15 amino acids in control and virus-infected plants. The outlined method aims to simplify the processing of MS data to quickly assess any modulation in amino acid levels in plants with a higher degree of confidence.

plant biology↗

bioRxiv2022

Spatiotemporal gene expression atlas of the extremophyte Schrenkiella parvula

Extremophytes are naturally selected to survive environmental stresses, but scarcity of genetic resources for them developed with spatiotemporal resolution limit their use in stress biology. Schrenkiella parvula is one of the leading extremophyte models with initial molecular genomic resources developed to study its tolerance mechanisms to high salinity. Here we present a transcriptome atlas for S. parvula with subsequent analyses to highlight its diverse gene expression networks associated with salt responses. We included spatiotemporal expression profiles, expression specificity of each gene, and co-expression and functional gene networks representing 115 transcriptomes sequenced from 35 tissue and developmental stages examining their responses before and after 27 salt treatments in our current study. The highest number of tissue-preferentially expressed genes were found in seeds and siliques while genes in seedlings showed the broadest expression profiles among developmental stages. Seedlings had the highest magnitude of overall transcriptomic responses to salinity compared to mature tissues and developmental stages. Differentially expressed genes in response to salt were largely mutually exclusive but shared common stress response pathways spanning across tissues and developmental stages. Our foundational dataset created for S. parvula representing a stress-adapted wild plant lays the groundwork for future functional, comparative, and evolutionary studies using extremophytes aiming to uncover novel stress tolerant mechanisms. SIGNIFICANCE STATEMENTConcerted transcriptomic responses coordinated across developmental stages and tissues are required to complete a plant lifecycle under salt stress. Transcriptomic resources created with spatiotemporal resolution for plants are rare and for stress-adapted plants rarer. We present a transcriptome atlas enabling discovery of genes and networks evolved as adaptations to salt stress in a model extremophyte, Schrenkiella parvula. The spatiotemporally resolved gene expression networks are largely non-overlapping but functionally connected through synergistic stress responsive pathways.

plant biology↗

bioRxiv2016

Modelling tree growth taking into account carbon source and sink limitations

Increasing CO2 concentrations are strongly controlled by the behaviour of undisturbed forests, which are believed to be a major current sink of atmospheric CO2. There are many models which predict forest responses to environmental changes but they are almost exclusively carbon source (i.e. photosynthesis) driven. Here we present a model for an individual tree that takes into account also the intrinsic limits of meristems and cellular growth rates, as well as control mechanisms within the tree that influence its diameter and height growth over time. This new framework is built on process-based understanding combined with differential equations solved by the Runge-Kutta-Fehlberg (RKF45) numerical method. It was successfully tested for stands of beech trees in two different sites representing part of a long-term forest yield experiment in Germany. This model provides new insights into tree growth and limits to tree height, and addresses limitations of previous models with respect to sink-limited growth.\n\nAuthor SummaryGreenhouse gas emissions, in particular of CO2, have emerged as one of the most important global concerns, and it is therefore important to understand the behaviour of forests as they absorb and store a very large quantity of carbon. Most models treat forests as boxes with growth only driven by photosynthesis, while their actual growth depends also on many other important processes such as the maximal rate at which individual cells can grow, the influences of temperature and soil moisture on these cells, and the control that the tree has on itself through endogenous signalling pathways. Therefore, and with inspiration from process-based understanding of the biological functioning of trees, we have developed a model which takes into account these different factors. We first use this knowledge and additional basic assumptions to derive a system of several equations which, when solved, enable us to predict the height and the radius of an individual tree at a given time, provided that we have enough information about its initial state and its surroundings. We use the Runge-Kutta-Fehlberg mathematical method to obtain a numerical solution and thus predict the development of the height and radius of an individual tree over time under specified conditions.

Plant Biology↗

bioRxiv2026

Comparative metabolomics of released pollen during dispersal reveals metabolic adaptations to cold and heat stress

Heat and cold stress can severely impair released pollen, reducing pollen viability and ultimately limiting fertilization and crop productivity. Following release, pollen is directly exposed to fluctuating environmental temperatures, necessitating adaptive metabolic mechanisms to sustain viability during dispersal. In response to temperature stress, pollen undergoes metabolic reprogramming that supports biochemical and physiological adaptation. However, the metabolic basis of pollen tolerance to extreme temperatures remains incompletely understood. In this study, biochemical assays combined with LC-MS-based untargeted metabolomic profiling were employed to investigate metabolic changes in released pollen exposed to low (15 {degrees}C) and high (35 {degrees}C) temperature stress. A total of 484 metabolites were detected, of which 147 were significantly altered between cold- and heat-stressed pollen, including 61 upregulated and 86 downregulated metabolites. Differentially regulated metabolites spanned multiple classes, including amino acids, flavonoids, long-chain fatty acids, sugars, and polyamines. Pathway enrichment analysis highlighted biologically relevant perturbations in amino acid and nucleic acid metabolism, including purine metabolism, arginine biosynthesis, and glutathione metabolism. Collectively, these findings demonstrate temperature-dependent metabolic adjustments in released pollen and provide new insights into the biochemical strategies underlying pollen tolerance to heat and cold stress. This work advances our understanding of pollen metabolic adaptation during dispersal and provides a foundation for identifying metabolic indicators relevant to crop fertility under changing climatic conditions. These findings provide a metabolomic framework for understanding pollen thermotolerance during dispersal and offer a resource for future studies on reproductive resilience under climate change.

plant biology↗

bioRxiv2026

Herbivory-induced alterations in cytosolic proteins of pigeon pea (Cajanus cajan) leaves

Insect herbivory triggers cytosolic proteome reprogramming by activating defense pathways and modulating key metabolic processes. We found that simulated herbivory in pigeon pea (Cajanus cajan) induced reactive oxygen species (ROS) production and molecular alterations within 12 hours (h) of post treatment. We compared the leaf proteome profiles of two cultivated genotypes, ICPL 332 (moderately resistant) and ICPL 87 (susceptible), using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) coupled with mass spectrometry (MS). More than 220 protein spots were detected in ICPL 332 and over 200 in ICPL 87. Comparative analysis revealed 75 differentially accumulated proteins (DAPs), of which 40 were consistently reproducible across biological replicates. These included 11 unique to ICPL 87, 9 unique to ICPL 332, and 10 common to both genotypes. Among the shared DAPs, ICPL 332 showed five upregulated and five downregulated, whereas ICPL 87 exhibited only two upregulated and eight downregulated. Functional categorization grouped DAPs into primary metabolism, stress response, and growth and development. Proteins related to primary metabolism were largely downregulated in both genotypes, while stress-associated proteins exhibited substantial downregulation in ICPL 87 compared to ICPL 332. Overall, the results demonstrate proteomic adjustments underlying defense responses in pigeon pea genotypes.

plant biology↗

bioRxiv2022

Temporal and spatial auxin responsive networks in maize primary roots

Auxin is a key regulator of root morphogenesis across angiosperms. To better understand auxin regulated networks underlying maize root development we have characterized auxin responsive transcription across two time points (30 and 120 minutes) and four regions of the primary root: the meristematic zone, elongation zone, cortex, and stele. Hundreds of auxin-regulated genes involved in diverse biological processes were quantified in these different root regions. In general, most auxin regulated genes are region unique and are predominantly observed in differentiated tissues compared to the root meristem. Auxin gene regulatory networks (GRNs) were reconstructed with these data to identify key transcription factors that may underlie auxin responses in maize roots. Additionally, Auxin Response Factor (ARF) subnetworks were generated to identify target genes which exhibit tissue or temporal specificity in response to auxin. These networks describe novel molecular connections underlying maize root development and provide a foundation for functional genomic studies in a key crop.

plant biology↗

bioRxiv2020

AINTEGUMENTA and AINTEGUMENTA-LIKE6 directly regulate floral homeotic and growth genes in young flowers

Arabidopsis flower primordia give rise to floral organ primordia in stereotypical positions within four concentric whorls. Floral organ primordia in each whorl undergo distinct developmental programs to become one of four organ types (sepals, petals, stamens, and carpels). The Arabidopsis transcription factors AINTEGUMENTA (ANT) and AINTEGUMENTA-LIKE6 (AIL6) play critical and partially overlapping roles during floral organogenesis. They are required for correct positioning of floral organ initiation, contribute to the specification of floral organ identity, and regulate the growth and morphogenesis of developing floral organs. To gain insight into the molecular means by which ANT and AIL6 contribute to floral organogenesis, we identified the genome-wide binding sites of both ANT and AIL6 in stage 3 flower primordia, the developmental stage at which sepal primordia become visible and class B and C floral homeotic genes are first expressed. AIL6 binds to a subset of ANT sites, suggesting that AIL6 regulates some but not all of the same target genes as ANT. ANT and AIL6 binding sites are associated with genes involved in many biological processes related to meristem and flower organ development. Comparison of genes associated with both ANT and AIL6 ChIP-Seq peaks and those differentially expressed after perturbation of ANT or AIL6 activity identified likely direct targets of ANT and AIL6 regulation. These include the floral homeotic genes APETALA3 (AP3) and AGAMOUS (AG) and four growth regulatory genes: BIG BROTHER (BB), ROTUNDIFOLIA3 (ROT3), ANGUSTIFOLIA3/GRF INTERACTING FACTOR (AN3/GIF1), and XYLOGLUCAN ENDOTRANSGLUCOLSYLASE/HYDROLASE9 (XTH9). One Sentence SummaryThe transcription factors ANT and AIL6 directly regulate genes involved in different aspects of flower development including genes that specify floral organ identity and those that regulate growth.

plant biology↗

bioRxiv2022

A Common Resequencing-Based Genetic Marker Dataset for Global Maize Diversity

Maize (Zea mays ssp. mays) populations exhibit vast amounts of genetic and phenotypic diversity. As sequencing costs have declined, an increasing number of projects have sought to measure genetic differences between and within maize populations using whole genome resequencing strategies, identifying millions of segregating single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels). Unlike older genotyping strategies like microarrays and genotyping by sequencing, resequencing should, in principle, frequently identify and score common genetic variants. However, in practice, different projects frequently employ different analytical pipelines, often employ different reference genome assemblies, and consistently filter for minor allele frequency within the study population. This constrains the potential to reuse and remix data on genetic diversity generated from different projects to address new biological questions in new ways. Here we employ resequencing data from 1,276 previously published maize samples and 239 newly resequenced maize samples to generate a single unified marker set of [~]366 million segregating variants and [~]46 million high confidence variants scored across crop wild relatives, landraces as well as tropical and temperate lines from different breeding eras. We demonstrate that the new variant set provides increased power to identify known causal flowering time genes using previously published trait datasets, as well as the potential to track changes in the frequency of functionally distinct alleles across the global distribution of modern maize.

plant biology↗

bioRxiv2020

Formation of flavone-based wooly fibres by glandular trichomes of Dionysia tapetodes.

Dionysia tapetodes, a small cushion-forming mountainous evergreen in the Primulaceae, possesses a vast surface-covering of long silky fibres forming the characteristic "wooly" farina. This contrasts with some related Primula which instead possess a powdery farina. Using a combination of cell biology and analytical chemical techniques, we provide a detailed insight of wooly farina formation by glandular trichomes that produce a mixture of flavone and substituted flavone derivatives, including hydroxyflavones. Conversely, our analysis show that the powdery form consist almost entirely of flavone. The wooly farina in D. tapetodes is extruded through specific sites at the surface of the glandular head cell, characterised by a small complete gap in the plasma membrane, cell wall and cuticle. The data is consistent with formation and thread elongation occurring from within the cell. The putative mechanism of wool thread formation and its stability is discussed.

plant biology↗

bioRxiv2026

Model-assisted high-throughput phenotyping of photosynthetic acclimation

Photosynthesis is a key determinant of crop productivity, yet conventional gas-exchange measurements are labor-intensive and unsuitable for high-throughput assessment of dynamic photosynthetic acclimation across large genotype panels. Consequently, genetic variation in photosynthetic acclimation remains poorly characterized and difficult to exploit in breeding programs. Here we present a computational pipeline that integrates rapid optical sensing (chlorophyll meters and hyperspectral reflectance) with a mechanistic model of photosynthetic protein-turnover to estimate dynamic nitrogen allocation among photosynthetic components. The pipeline was demonstrated using 60 winter wheat (Triticum aestivum L.) cultivars sampled at 10 time points spanning leaf emergence to senescence. Uncertainties associated with each pipeline component were quantified and benchmarked against gas-exchange ground-truth measurements under three controlled-environment light and temperature regimes. Dynamic nitrogen allocation to light harvesting, electron transport, and carboxylation was characterized using three biologically interpretable parameters: maximum synthesis rate, degradation rate, and age-dependent decline in synthesis. Although hyperspectral models showed moderate predictive accuracy for photosynthetic capacity, prediction errors were predominantly random, allowing robust parameter estimation when observations across the leaf lifespan were integrated. The pipeline successfully resolved genotype-by-environment interactions in photosynthetic acclimation, with environmental and interaction effects contributing more strongly than genotype main effects to nitrogen dynamics. These results demonstrate a scalable, uncertainty-aware sensor-to-trait architecture for dynamic physiological phenotyping that enables high-throughput germplasm screening across diverse environments and provides novel physiological selection targets for improving crop adaptation under variable climates.

plant biology↗

bioRxiv2026

From chromosome-scale assembly to the mappable genome of rubber dandelion: chromosome reorganization, rubber-pathway coordination, and domestication traits

Natural rubber supply depends almost entirely on one tropical tree, motivating development of temperate alternatives. Rubber dandelion (Taraxacum kok-saghyz Rodin) is the leading candidate, with comparatively well characterized rubber biosynthesis pathways, but its large, repeat-rich genome has left breeding genomics far behind pathway biology. In response, we assembled OSU TarKok 3.0, a 1.19-Gb nuclear reference in which eight chromosome-scale scaffolds contain 98% of the sequence. Continuity within chromosomes improved markedly, with contig N50 rising from 1.3 to 37.8 Mb, and conserved gene-space recovery improved accordingly. Macrosynteny showed strong chromosome conservation within Taraxacum and, when compared to lettuce, displayed four nearly intact and four composite chromosomes, a signature compatible with descending dysploidy accompanied by rearrangement rather than a single end-to-end fusion. Across nine Cichorieae genomes, none of six surveyed rubber-related gene families was uniquely enlarged in rubber dandelion. Instead, a cis-prenyltransferase locus, a rubber transferase activator, and three small rubber particle protein genes were enriched in underground tissues and grouped with rubber elongation factor in a latex-associated co-expression module, favoring coordinated pathway deployment over species-specific family expansion. Intersecting uniquely mappable and nonrepetitive sequence defined the mappable genome, approximately 210 Mb or 18% of the assembly, within which markers can be interpreted allelically. Mapping in an independent F2 family of 83 plants identified a chromosome 1 locus for filled-seed production under restricted cross-pollination, whereas herbicide response yielded no significant locus in this design. OSU TarKok 3.0 links chromosome reorganization, pathway deployment, and domestication traits into one framework for improving an outcrossing crop.

plant biology↗

bioRxiv2026

Crop yields under simulated nuclear winter: a growth chamber experiment

A global nuclear war could inject soot into the stratosphere, blocking sunlight and causing rapid cooling. Assessments of the resulting agricultural collapse rely on crop models never validated under such conditions. We grew wheat, canola, and potato in growth chambers simulating the light and temperature of an extreme nuclear winter at tropical and temperate sites. In the tropical chamber (18-20 {degrees}C, 200 mol m-2 s-1 PAR), all three crops produced viable yields. Wheat yielded 2.1-2.3 t/ha (n=3 well-watered, n=3 water-stressed pots), 60% of the global average, and single-pot observations of canola and potato suggested biological yields comparable to global averages. In the temperate chamber simulating nuclear winter irradiance (60-360 mol m-2 s-1), wheat stems collapsed under their own weight. Although hand-harvesting recovered 0.6-2.8 t/ha of grain, mechanical field harvest of a flat canopy would recover substantially less. This failure mode was not observed in a higher-light control chamber and is not captured by existing crop models, which may therefore overestimate temperate cereal production under nuclear winter. Canola produced comparable yields under both temperate light regimes without lodging. Empirical screening of additional staples is needed to identify which remain viable under nuclear winter.

plant biology↗

bioRxiv2020

Linkage mapping and QTL analysis of flowering time using ddRAD sequencing with genotype error correction in Brassica napus

Brassica napus is an important oilseed crop cultivated worldwide. During domestication and breeding of B. napus, flowering time has been a target of selection because of its substantial impact on yield. Here we use double digest restriction-site associated DNA sequencing (ddRAD) to investigate the genetic basis of flowering in B. napus. An F2 mapping population was derived from a cross between an early-flowering spring type and a late-flowering winter type. Flowering time in the mapping population differed by up to 25 days between individuals. High genotype error rates persisted after initial quality controls, as suggested by a genotype discordance of ∼12% between biological sequencing replicates. After genotype error correction, a linkage map spanning 3,605.70 cM and compromising 14,630 single nucleotide polymorphisms (SNPs) was constructed. A quantitative trail locus (QTL) on chromosome C2 was detected in the vicinity of flowering time genes including FT and FLC. These findings demonstrate the effectiveness of the ddRAD approach to sample the B. napus genome. Our results also suggest that ddRAD genotype error rates can be higher than expected in F2 populations. Quality filtering and genotype correction and imputation can substantially reduce these error rates and allow effective linkage mapping and QTL analysis.Competing Interest StatementBASF supported this work and employs SR.View Full Text

plant biology↗

bioRxiv2025

Automated detection and quantification of two-spotted spider mite life stages using computer vision for high-throughput in vitro assays

The two-spotted spider mite (Tetranychus urticae Koch) is a globally significant agricultural pest with high reproductive capacity, rapid development, and frequent evolution of miticide resistance. Breeding and selection of resistant host cultivars represent a promising complement to chemical control, but widespread adoption is limited primarily due to the labor-intensive nature of conventional in vitro phenotyping methods. Here, we present a high-throughput, semi-automated image analysis pipeline integrating the Blackbird CNC Microscopy Imaging Robot with computer vision models for mite life stage identification. We developed a publicly available dataset of over 1,500 annotated images (nearly 32,000 labeled instances) spanning five biologically relevant classes across 10 host species and >25 cultivars. Three YOLO11-based object detection models (three-, four-, and five-class configurations) were trained and evaluated using real and synthetic data. The three-class model achieved the highest overall performance on the hold out test set (precision = 0.875, recall = 0.871, mAP50 = 0.883), with detection accuracy robust to host background and moderate object densities. Application to miticidal assays demonstrated reliable fecundity estimation but reduced accuracy for mortality assessment due to misclassification of dead mites. In hop cultivar assays, the pipeline detected significant differences in fecundity, aligning with manual counts (R2 [≥] 0.98). Performance declined on hosts absent from training data and at densities exceeding [~]80 objects per image, underscoring the need for host-specific fine-tuning and density-aware assay experimental design. By enabling rapid, standardized, and reproducible quantification of mite life stages, this system offers a scalable alternative to manual scoring, particularly for resistance breeding programs targeting antibiosis traits. Our approach addresses major throughput bottlenecks in T. urticae phenotyping and establishes a framework for integrating automated imaging into broader pest management and plant breeding pipelines. Dataset, code, and trained models are publicly available to facilitate adoption and extension.

plant biology↗

bioRxiv2022

Mutations in OsRZF1, encoding a zinc-finger protein, causes reduced magnesium uptake in roots and translocation to shoots in rice

Magnesium (Mg) homeostasis is critical for maintaining many biological processes, but little information is available to comprehend the molecular mechanisms regulating Mg concentration in rice (Oryza sativa). To make up for the lack of information, we aimed to identify mutants defective in Mg homeostasis through a forward genetic approach. As a result of the screening of about 3,000 M2 seedlings mutated by ion-beam irradiation, we found a rice mutant that showed reduced Mg content in leaves and slightly increased Mg content in roots. Radiotracer 28Mg experiments showed that this mutant, named low magnesium content 1 (LMGC1), has decreased Mg2+ influx in the root and Mg2+ translocation from root to shoot. The MutMap method identified 7.4 kbp deletion in the LMGC1 genome leading to a loss of two genes. Genome editing using CRISPR-Cas9 further revealed that one of the two lost genes, a gene belonging to RanBP2-type zinc finger family, was the causal gene of the low-Mg phenotype. Considering this gene, named OsRZF1, has never been reported to be involved in ion transport, the phenotype of LMGC1 would be associated with a novel mechanism of Mg homeostasis in plants.

plant biology↗

bioRxiv2019

Molecular characterization of Chlamydomonas reinhardtii telomeres and telomerase mutants

Telomeres are repeated sequences found at the end of the linear chromosomes of most eukaryotes and are required for chromosome integrity. They shorten with each cell division because of the end-replication problem. Expression of the reverse transcriptase telomerase allows for extension of telomeric repeats to counteract telomere shortening. Although Chlamydomonas reinhardtii, a photosynthetic unicellular green alga, is widely used as a model organism in photosynthesis and flagella research, and for biotechnological applications, the biology of its telomeres has not been investigated in depth. Here, we show that the C. reinhardtii (TTTTAGGG)n telomeric repeats are mostly non-degenerate and that the telomeres form a protective structure, ending with a 3' overhang. While telomere size and length distributions are stable under various standard growth conditions, they vary substantially between 12 genetically close reference strains. Finally, we identify CrTERT, the gene encoding the catalytic subunit of telomerase and show that mutants of this gene display an \"ever shortening telomere\" phenotype and eventually enter replicative senescence, demonstrating that telomerase is required for long-term maintenance of telomeres in C. reinhardtii.

plant biology↗