Twenty-four-nucleotide siRNAs produce heritable trans-chromosomal methylation in F1 Arabidopsis hybrids.
نویسندگان
چکیده
Hybrid Arabidopsis plants undergo epigenetic reprogramming producing decreased levels of 24-nt siRNAs and altered patterns of DNA methylation that can affect gene expression. Driving the changes in methylation are the processes trans-chromosomal methylation (TCM) and trans-chromosomal demethylation (TCdM). In TCM/TCdM the methylation state of one allele is altered to resemble the other allele. We show that Pol IV-dependent sRNAs are required to establish TCM events. The changes in DNA methylation and the associated changes in sRNA levels in the F1 hybrid can be maintained in subsequent generations and affect hundreds of regions in the F2 epigenome. The inheritance of these altered epigenetic states varies in F2 individuals, resulting in individuals with genetically identical loci displaying different epigenetic states and gene expression profiles. The change in methylation at these regions is associated with the presence of sRNAs. Loci without any sRNA activity can have altered methylation states, suggesting that a sRNA-independent mechanism may also contribute to the altered methylation state of the F1 and F2 generations.
منابع مشابه
Inheritance of Trans Chromosomal Methylation patterns from Arabidopsis F1 hybrids.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 113 44 شماره
صفحات -
تاریخ انتشار 2016