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Insertion of Short L1 Sequences Generates Inter-strain Histone Acetylation Differences in the Mouse

Overview
Journal Mob DNA
Publisher Biomed Central
Specialty Genetics
Date 2024 May 10
PMID 38730323
Authors
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Abstract

Background: Gene expression divergence between populations and between individuals can emerge from genetic variations within the genes and/or in the cis regulatory elements. Since epigenetic modifications regulate gene expression, it is conceivable that epigenetic variations in cis regulatory elements can also be a source of gene expression divergence.

Results: In this study, we compared histone acetylation (namely, H3K9ac) profiles in two mouse strains of different subspecies origin, C57BL/6 J (B6) and MSM/Ms (MSM), as well as their F1 hybrids. This identified 319 regions of strain-specific acetylation, about half of which were observed between the alleles of F1 hybrids. While the allele-specific presence of the interferon regulatory factor 3 (IRF3) binding sequence was associated with allele-specific histone acetylation, we also revealed that B6-specific insertions of a short 3' fragment of LINE-1 (L1) retrotransposon occur within or proximal to MSM-specific acetylated regions. Furthermore, even in hyperacetylated domains, flanking regions of non-polymorphic 3' L1 fragments were hypoacetylated, suggesting a general activity of the 3' L1 fragment to induce hypoacetylation. Indeed, we confirmed the binding of the 3' region of L1 by three Krüppel-associated box domain-containing zinc finger proteins (KZFPs), which interact with histone deacetylases. These results suggest that even a short insertion of L1 would be excluded from gene- and acetylation-rich regions by natural selection. Finally, mRNA-seq analysis for F1 hybrids was carried out, which disclosed a link between allele-specific promoter/enhancer acetylation and gene expression.

Conclusions: This study disclosed a number of genetic changes that have changed the histone acetylation levels during the evolution of mouse subspecies, a part of which is associated with gene expression changes. Insertions of even a very short L1 fragment can decrease the acetylation level in their neighboring regions and thereby have been counter-selected in gene-rich regions, which may explain a long-standing mystery of discrete genomic distribution of LINEs and SINEs.

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References
1.
Hirata M, Ichiyanagi T, Katoh H, Hashimoto T, Suzuki H, Nitta H . Sequence divergence and retrotransposon insertion underlie interspecific epigenetic differences in primates. Mol Biol Evol. 2022; . PMC: 9577543. DOI: 10.1093/molbev/msac208. View

2.
Ichiyanagi K . Epigenetic regulation of transcription and possible functions of mammalian short interspersed elements, SINEs. Genes Genet Syst. 2013; 88(1):19-29. DOI: 10.1266/ggs.88.19. View

3.
Ichiyanagi T, Katoh H, Mori Y, Hirafuku K, Boyboy B, Kawase M . B2 SINE Copies Serve as a Transposable Boundary of DNA Methylation and Histone Modifications in the Mouse. Mol Biol Evol. 2021; 38(6):2380-2395. PMC: 8136502. DOI: 10.1093/molbev/msab033. View

4.
Pezic D, Manakov S, Sachidanandam R, Aravin A . piRNA pathway targets active LINE1 elements to establish the repressive H3K9me3 mark in germ cells. Genes Dev. 2014; 28(13):1410-28. PMC: 4083086. DOI: 10.1101/gad.240895.114. View

5.
Feschotte C . Transposable elements and the evolution of regulatory networks. Nat Rev Genet. 2008; 9(5):397-405. PMC: 2596197. DOI: 10.1038/nrg2337. View