Biology subjects

Rütjes, T.

Publications and source records attributed to Rütjes, T..

3 recordsLinked to original sources

bioRxiv2025

Golden Promise-rapid, a fast-cycling barley genotype with high transformation efficiency

The spring barley cultivar Golden Promise (GP) is the major reference genotype for transformation due to its high transformability and availability of a reference genome. However, GP is characterized by a long generation cycle and stress susceptibility under non-optimal growth conditions because it carries a mutation at the floral inducer Photoperiod-H1 (Ppd-H1). Previously, we showed that a GP introgression line, Golden Promise-fast (GP-fast), generated by introducing the wild-type Ppd-H1 allele from the winter barley cultivar Igri, exhibits early flowering and improved stress resilience. In this study, we generated a fast-cycling genotype, Golden Promise-rapid (GP-rapid), isogenic to GP with high transformation efficiency. We conducted two backcrosses of GP-fast to reduce the residual Igri genome. The resulting genotype contains only a single introgression of approximately 0.6 Mbp at the Ppd-H1 locus on chromosome 2H. Under speed breeding conditions, its generation time was reduced to 63 days (25% shorter than GPs 84 days). Parallel transformation of GP, GP-fast, and GP-rapid using CRISPR/Cas9-mediated genome editing of Ppd-H1 revealed high regeneration and transformation efficiencies of GP-rapid, comparable to GP. Overall, we report on the development of a fast-cycling GP isogenic line as a research tool for efficient generation of transgenic and gene-edited barley plants. HighlightsA new fast-cycling barley genotype, GP-rapid, reduces generation time by 25% while retaining high transformation efficiency, advancing functional genomic studies in barley.

plant biology↗

bioRxiv2025

A chromosome-scale genome assembly of Hordeumerectifolium: genomic, transcriptomic and anatomicaladaptations to drought in a wild barley relative

O_LIWild crop relatives are valuable genetic resources for improving stress adaptation in cultivated species, but their effective use depends on high-quality reference genomes integrated with phenotypic and molecular datasets. Hordeum erectifolium, a wild relative of barley (H. vulgare), is adapted to intermittent and prolonged drought and saline soils, making it an excellent model for stress-adaptation research. C_LIO_LIWe assembled a chromosome-scale, annotated reference genome of H. erectifolium comprising 3.85 Gbp, and identified 71,475 genes supported by a tissue-specific gene expression atlas. Comparative morphological, physiological, and transcriptomic analyses under water limitation were conducted with cultivated and wild barley. C_LIO_LIH. erectifolium displayed a greater density of leaf veins and sclerenchyma cells, alongside rapid leaf rolling upon dehydration. Genomic comparisons revealed structural variations, independent transposon-driven evolution, and copy number expansions of desiccation-responsive gene families relative to barley. The transcriptional responses of H. erectifolium and barley to water limitation suggested contrasting drought-adaptation strategies: metabolic down-regulation and survival prioritization in H. erectifolium versus maintenance of metabolic activity and competitiveness in barley. C_LIO_LIOur data suggest that H. erectifolium is genetically primed for survival under drought through anatomical adaptations, gene family expansion, efficient shutdown of growth-related metabolism, and rapid recovery upon rehydration. C_LI

evolutionary biology↗

bioRxiv2023

EARLY MATURITY 7 modifies the circadian clock and photoperiod sensitivity in barley

Breeding for variation in photoperiod response is crucial to adapt crop plants to novel environments. Plants measure changes in day length by the circadian clock, an endogenous timekeeper that allows plants to anticipate changes in diurnal and seasonal light-dark cycles. Here, we describe the early maturity 7 (eam7) mutation in barley, which interacts with natural variation at PHOTOPERIOD 1 (Ppd-H1) to cause early flowering independent of the photoperiod. We identify LIGHT-REGULATED WD 1 (LWD1) as a putative candidate to underly the eam7 locus in barley as supported by genetic mapping and CRISPR-Cas9 generated lwd1 mutants. Mutations in eam7 cause a significant phase advance and a misregulation of core clock and clock output genes under diurnal conditions. Early flowering correlated with an upregulation of Ppd-H1 during the night and consequent induction of the florigen FLOWERING LOCUS T1 under short days. We propose that EAM7 controls photoperiodic flowering in barley by controlling the light input into the clock and diurnal expression patterns of the major photoperiod response gene Ppd-H1.

plant biology↗