Biology subjects

Watkins, E.

Publications and source records attributed to Watkins, E..

6 recordsLinked to original sources

bioRxiv2025

Improving Perennial Ryegrass Transformation Protocols with Developmental Regulators

The development of genetically modified (GM) or gene edited (GE) turfgrass requires transformation systems that are both efficient and broadly applicable across genotypes. However, traditional Agrobacterium-mediated callus culture methods remain limited by low transformation efficiency, extended culture durations, and strong genotype dependence. In this study, we compare a modified classical callus culture protocol with an approach that incorporates the developmental regulator genes WUSCHEL2 (wus2) and BABY BOOM (bbm), along with an inducible Cre recombinase and a dual luciferase assay to test variable promoter strengths in perennial ryegrass (Lolium perenne L.). We show that traditional protocols failed to regenerate plants, despite successful callus formation and transgene expression. In contrast, the developmental regulator system enabled efficient callus induction and plant regeneration independent of genotype. This optimized protocol significantly reduces the time and genotype constraints of perennial ryegrass transformation, offering a practical platform for advanced genetic engineering applications of an important turf and forage grass.

plant biology↗

bioRxiv2023

Seryl-butyrate: a prodrug that enhances butyrate's oral bioavailability and suppresses autoimmune arthritis and experimental autoimmune encephalomyelitis

Butyrate, a metabolite produced by commensal bacteria, has been intensively studied for its immunomodulatory effects on various immune cells, including T regulatory cells, macrophages, and dendritic cells. Butyrates development as a drug has been limited by its poor oral bioavailability due to its rapid metabolism in the gut, its low potency and thus high dosing, and its foul smell and taste. By simply esterifying butyrate to serine (O-butyryl-L-serine, SerBut), a design based on the concept of utilizing amino acid transporters to escape the gut and enhance systemic uptake thus increasing bioavailability, we developed an odorless and tasteless compound for oral administration. In the collagen antibody-induced arthritis (CAIA) and experimental autoimmune encephalomyelitis (EAE) murine models of rheumatoid arthritis and multiple sclerosis, we demonstrated that SerBut significantly ameliorated disease severity, modulated key immune cell populations both systemically and in disease-associated tissues, and reduced inflammatory responses without compromising global immune response to vaccination. Our findings highlight SerBut as a promising next-generation therapeutic agent for autoimmune and inflammatory diseases.

bioengineering↗

bioRxiv2020

Evaluating the Effects of Propiconazole on Hard Fescue (Festuca brevipila) via RNA sequencing and Liquid Chromatography Mass Spectrometry

Propiconazole is often used to remove fungal endophytes from turfgrass to study the effects of Epichloe endophytes. However, besides a fungicidal effect, propiconazole can bind to the genes in the cytochrome P450 family and affect the biosynthesis of brassinosteroids. For this reason, outside of fungicidal application, propiconazole has also been used as plant growth regulator. In this study, we used a combination of RNA sequencing and liquid chromatography-mass spectrometry (LC-MS) to study how hard fescue (Festuca brevipila) responded to the high dose of propiconazole treatment. To test the long-term effect of the heavy use of propiconazole on plants, we inoculated with Microdochium nivale (causal agent of pink snow mold) half year post the last fungicide application. Propiconazole-treated plants showed enhanced pink snow mold resistance. This study suggested that the high dose use of propiconazole fungicide resulted in phenotypic and physiological changes in the plant such as slow growth and change in disease resistance. Genes and pathways affected by propiconazole identified in this study provide turfgrass breeders new information for genetic improvement of hard fescue and also provide turfgrass management new ways to control turfgrass diseases.

plant biology↗

bioRxiv2020

Building a Reference Transcriptome for the Hexaploid Hard Fescue Turfgrass (Festuca brevipila) Using a Combination of PacBio IsoSeq and Illumina Sequencing

BackgroundHard fescue (Festuca brevipila Tracey, 2n=6x=42) is a cool season turfgrass with a fine leaf texture that performs well under low-input management. Breeding and genetics studies of F. brevipila have been limited due to the complexity of its hexaploid genome. To advance our knowledge of F. brevipila genomics, we used PacBio isoform sequencing to develop a reference transcriptome for this species. ResultsHere, we report the F. brevipila reference transcriptome generated from root, crown, leaf, and inflorescence tissues. We obtained 59,510 full-length transcripts, of which 38,556 were non-redundant full-length transcripts. The longest and shortest transcripts were 11,487 and 58 bp, respectively. Distribution of synonymous distances among paralogs within F. brevipila suggested highly similar subgenomes that are difficult to distinguish from sequencing errors. To evaluate the phylogenetic relationships among F. brevipila and close relatives, we sequenced three additional transcriptomes using closely related species on an Illumina platform. The results of our phylotranscriptomic analysis supported the close relationships among F. brevipila (6x), Festuca ovina (4x), Festuca ovina subsp. ovina (2x), and Festuca valesiaca (2x), with high levels of discordance among gene trees. ConclusionsOverall, the F. brevipila PacBio Isoseq reference transcriptome provided the foundation for transcriptome studies and allowed breeders a resource for gene discovery in this important turfgrass species.

plant biology↗

bioRxiv2020

DNA Content and Ploidy Estimation of Festuca ovina Accessions by Flow Cytometry

Festuca ovina is a fine fescue that is used as a low-input turfgrass. The ploidy levels of F. ovina accessions held by the USDA National Plant Germplasm System (NPGS) are unknown, limiting the use of the germplasm in breeding programs. The objective of this study was to determine DNA content and estimate ploidy of these 127 accessions. Among the accessions, we identified a wide range of ploidy levels from diploid to octoploid. We also found the accessions with higher ploidy levels usually had larger seed size. These results will be informative to plant breeders and researchers using germplasm from the F. ovina collection and point to challenges in maintaining polyploid, outcrossing germplasm seed stocks in common nurseries.

plant biology↗

bioRxiv2019

Chloroplast Genome Sequencing and Comparative Analysis for Five Species of the Turfgrass Fine Fescues (Festuca L., Poaceae)

Fine fescues (Festuca L., Poaceae) are turfgrass species that perform well in low-input environments. Based on morphological characteristics, the most commonly-utilized fine fescues are divided into five taxa: three are subspecies within F. rubra L. and the remaining two are treated as species within the F. ovina L. complex. Morphologically, these five taxa are very similar, both identification and classification of fine fescues remain challenging. In an effort to develop identification methods for fescues, we used flow cytometry to estimate genome size, ploidy level, and sequenced the chloroplast genome of all five taxa. Fine fescue chloroplast genome sizes ranged from 133,331 to 133,841 bp and contained 113 to 114 genes. Phylogenetic relationship reconstruction using whole chloroplast genome sequences agreed with previous work based on morphology. Comparative genomics suggested unique repeat signatures for each fine fescue taxon that could potentially be used for marker development for taxon identification.

plant biology↗