A complex network of interactions governs DNA methylation at telomeric regions. Issue 3 (21st January 2022)

• Record Type: Journal Article
• Authors: Farrell, Colin; Vaquero-Sedas, María I; Cubiles, María D; Thompson, Michael; Vega-Vaquero, Alejandro; Pellegrini, Matteo; Vega-Palas, Miguel A
• Is Part Of: Nucleic acids research. Volume 50:Issue 3(2022)
• Page Start: 1449
• Page End: 1464
• Publication Date: 2022-01-21
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gkac012
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract: DNA methylation modulates telomere function. In Arabidopsis thaliana, telomeric regions have a bimodal chromatin organization with unmethylated telomeres and methylated subtelomeres. To gain insight into this organization we have generated TAIR10-Tel, a modified version of the Arabidopsis reference genome with additional sequences at most chromosome ends. TAIR10-Tel has allowed us to analyse DNA methylation at nucleotide resolution level in telomeric regions. We have analysed the wild-type strain and mutants that encode inactive versions of all currently known relevant methyltransferases involved in cytosine methylation. These analyses have revealed that subtelomeric DNA methylation extends 1 to 2 kbp from Interstitial Telomeric Sequences (ITSs) that abut or are very near to telomeres. However, DNA methylation drops at the telomeric side of the telomere-subtelomere boundaries and disappears at the inner part of telomeres. We present a comprehensive and integrative model for subtelomeric DNA methylation that should help to decipher the mechanisms that govern the epigenetic regulation of telomeres. This model involves a complex network of interactions between methyltransferases and subtelomeric DNA sequences.