Publications by authors named "Peter Ryder"

Plastid ribosomal proteins (PRPs) can play essential roles in plastid ribosome functioning that affect plant function and development. However, the roles of many PRPs remain unknown, including elucidation of which PRPs are essential or display redundancy. Here, we report that the nuclear-encoded PLASTID RIBOSOMAL PROTEIN L5 (PRPL5) is essential for early embryo development in A.

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Article Synopsis
  • The 45S rRNA genes are large repetitive elements in eukaryotic genomes, with many remaining transcriptionally inactive, possibly serving as back-up copies for ribosome production and nuclear organization.
  • Using Cas9 genome editing in Arabidopsis thaliana, researchers successfully reduced 45S rDNA copy numbers by up to 90% while maintaining normal rRNA transcription levels, indicating a gene dosage compensation mechanism at play.
  • Although the overall genome integrity was preserved, one line exhibited a chromosome segmental duplication, and transcriptome analysis revealed shared dysregulated genes and pathways across independent low copy number lines, highlighting the implications of reduced rDNA copy number on cellular processes and development.
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Background: The phenomenon of heterosis is critical to plant breeding and agricultural productivity. Heterosis occurs when F1 hybrid offspring display quantitative improvements in traits to levels that do not occur in the parents. Increasing the genome dosage (i.

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RNA-guided endonuclease-mediated targeted mutagenesis using the clustered regularly interspersed short palindromic repeats (CRISPR)/Cas9 system has been successful at targeting specific loci for modification in plants. While polyploidy is an evolutionary mechanism enabling plant adaptation, the analysis of gene function in polyploid plants has been limited due to challenges associated with generating polyploid knockout mutants for all gene copies in polyploid plant lines. This study investigated whether CRISPR/Cas9 mediated targeted mutagenesis can generate nulliplex tetraploid mutant lines in Arabidopsis thaliana, while also comparing the relative efficiency of targeted mutagenesis in tetraploid (4x) versus diploid (2x) backgrounds.

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Heterosis is the phenomenon whereby hybrid offspring of genetically divergent parents display superior characteristics compared with their parents. Although hybridity and polyploidy can influence heterosis in hybrid plants, the differential contributions of hybridity vs polyploidy to heterosis effects remain unknown. To address this question, we investigated heterosis effects on rosette size and growth rate of 88 distinct F1 lines of Arabidopsis thaliana consisting of diploids, reciprocal triploids and tetraploids in isogenic and hybrid genetic contexts.

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