Skip to Main content Skip to Navigation
Journal articles

Gene dosage compensation of rRNA transcript levels in Arabidopsis thaliana lines with reduced ribosomal gene copy number

Abstract : The 45S rRNA genes (rDNA) are amongst the largest repetitive elements in eukaryotic genomes. rDNA consists of tandem arrays of rRNA genes, many of which are transcriptionally silenced. Silent rDNA repeats may act as ‘back-up’ copies for ribosome biogenesis and have nuclear organization roles. Through Cas9-mediated genome editing in the Arabidopsis thaliana female gametophyte we reduced 45S rDNA copy number to a plateau of ∼10%. Two independent lines had rDNA copy numbers reduced by up to 90% at the T7 generation, named Low Copy Number (LCN) lines. Despite drastic reduction of rDNA copies, rRNA transcriptional rates and steady-state levels remained the same as wild type plants. Gene dosage compensation of rRNA transcript levels was associated with reduction of silencing histone marks at rDNA loci and altered Nucleolar Organiser Region 2 organization. While overall genome integrity of LCN lines appears unaffected, a chromosome segmental duplication occurred in one of the lines. Transcriptome analysis of LCN seedlings identified several shared dysregulated genes and pathways in both independent lines. Cas9 genome editing of rRNA repeats to generate LCN lines provides a powerful technique to elucidate rDNA dosage compensation mechanisms and impacts of low rDNA copy number on genome stability, development, and cellular processes.
Complete list of metadata

https://hal-univ-perp.archives-ouvertes.fr/hal-03133170
Contributor : Martin Rosalie <>
Submitted on : Friday, February 5, 2021 - 4:49:47 PM
Last modification on : Monday, March 29, 2021 - 2:47:40 PM
Long-term archiving on: : Friday, May 7, 2021 - 8:28:53 AM

File

koab020.pdf
Files produced by the author(s)

Identifiers

Citation

Francesca Lopez, Antoine Fort, Luca Tadini, Aline Probst, Marcus Mchale, et al.. Gene dosage compensation of rRNA transcript levels in Arabidopsis thaliana lines with reduced ribosomal gene copy number. The Plant cell, American Society of Plant Biologists (ASPB), In press, ⟨10.1093/plcell/koab020⟩. ⟨hal-03133170⟩

Share

Metrics