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Biology subjects

Glover, K.

Publications and source records attributed to Glover, K..

3 recordsLinked to original sources

Genome-wide Screening Identifies Unique Host-Directed Drugs and Pro-viral Signalling Pathways for SARS-CoV-2

SARS-CoV-2 is a positive-sense RNA virus and was responsible for the devastating COVID-19 pandemic. Although the current disease burden is less severe, there are limited treatment options, significant gaps in knowledge, and a looming threat of the emergence of variants and future pandemics. To address these challenges, we performed genome-wide CRISPR knockout screens in a novel human lung cell line NCI-H23ACE2, as well as in HEK293TACE2 cells, with SARS-CoV-2 Wuhan virus, with the aim of identifying host-dependency factors that could predict effective antivirals. We identified four host-directed drugs, donepezil, dH-ergocristine, trametinib and sorafenib, that could potentially be repurposed to treat coronavirus infections. Three of the drugs inhibited SARS-CoV-2, HCoV-229E, and HCoV-OC43, suggesting they could be used as pan-coronavirus antivirals. We also confirmed that SARS-CoV-2 relies on the NRAS/Raf/MEK/ERK signaling pathway for its replication. Our study highlights the robustness and efficiency of a bilateral approach of gene silencing and antiviral screening to identify host-dependency factors and effective antivirals.

microbiology↗

A century of breeding has preserved genetic variation, accumulated favorable alleles, and shaped the Rht gene portfolio in North American spring wheat

Hard red spring wheat (HRSW) is an important market class of wheat in North America with a rich history of breeding. We genotyped 1,013 HRSW lines representing a century of breeding material using a SNP array and targeted KASP genotyping to assess the changes in genetic diversity and Rht genes in HRSW from North America. Results show that early breeding efforts broadened an initially narrow gene pool derived from a few founders and subsequently maintained the genetic diversity. Analysis of Rht genes revealed that Rht-D1b was the predominant semi-dwarf allele from introduction of the Green Revolution genes (Rht-B1 and Rht-D1) in 1960s until the FHB epidemics of 1990s, when most breeding programs shifted to Rht-B1b. However, adoption of Rht-B1b and Rht-D1b remains low in some regions of the Great Plains. The dwarf alleles at GA-sensitive Rht24 and Rht25 have persisted in the region at low frequencies before the introduction of Green Revolution genes and have increased in frequency in recent decades. We also analyzed the effect of Rht genes on plant height (PH) in the HRSW growing region and found that Rht-B1b or Rht-D1b results in [~]12% reduction in PH, which decreases to [~]9% in dry environments. Notably, combining dwarfing alleles at Rht24 and Rht25 reduced height by [~]6% in dry environments, suggesting an alternative approach for reducing PH. Our analysis also revealed significant genetic interactions between Rht-B1 and Rht25, as well as between Rht-D1 and Rht24, which could help fine-tune PH for different environments by employing appropriate Rht combinations. Furthermore, our results demonstrate positive selection for photoperiod sensitivity in recent decades, particularly in high-latitude regions. This study provides a valuable genomic resource, and the findings enhance our understanding of past breeding efforts while offering insights to guide future plant breeding strategies.

plant biology↗

Genetic Gains from Sixty Years of Spring Wheat Breeding in the Northern Plains of the US

Evaluating genetic gains over time is essential for assessing the success of breeding programs and refining strategies for ongoing improvement. Hard red spring (HRS) wheat is an important wheat class in the US and is primarily grown in the Northern Great Plains. Despite a long history of breeding efforts in this region, long-term quantification of genetic gains for key traits has remained limited. This study analyzes over sixty years of data from the USDA-coordinated Hard Red Spring Wheat Uniform Regional Nursery (HRSWURN) to evaluate genetic advancements in agronomic traits across multiple phases. A significant positive genetic gain of 0.61% per annum was observed for grain yield in HRS wheat released in the Northern US region, which is lower than the expected gains needed to meet future wheat demand. The change was 0.07% for test weight, -0.04% for days to heading, and -0.16% for plant height. Notably, sustained yield improvements have not affected grain protein levels since they were first measured in 1995, indicating that ongoing selection has effectively balanced grain yield and protein despite their negative correlation (r = -0.31). Assessment of genetic gains over 20-year phases suggested slowing rates of genetic gains for grain yield but did not indicate any plateaus. The realized genetic gains were generally higher for individual breeding programs when breeding for target environments, with the public breeding program in Minnesota observing gains of approximately 1% per annum. These findings highlight the significant impact of long-term breeding efforts and offer valuable insights for refining future breeding strategies.

plant biology↗