A DNA adenine demethylase impairs PRC2-mediated repression of genes marked by a specific chromatin signature.

Background: The Fe (II)- and α-ketoglutarate-dependent AlkB family dioxygenases are implicated in nucleotide demethylation. AlkB homolog1 (ALKBH1) is shown to demethylate DNA adenine methylation (6mA) preferentially from single-stranded or unpaired DNA, while its demethylase activity and function in the chromatin context are unclear.

Results: Here, we find that loss-of-function of the rice ALKBH1 gene leads to increased 6mA in the R-loop regions of the genome but has a limited effect on the overall 6mA level.

An enhanced network of energy metabolism, lysine acetylation, and growth-promoting protein accumulation is associated with heterosis in elite hybrid rice.

Heterosis refers to the superior performance of a hybrid compared with its parental lines. Although several genetic and molecular models have been proposed to explain heterosis, it remains unclear how hybrid cells integrate complementary gene expression or activity to drive heterotic growth. In this work, we show that accumulation of growth-promoting and energy metabolism proteins, enhanced energy metabolism activities, and increased protein lysine acetylation were associated with superior growth of the panicle meristem in the elite hybrid rice Shanyou 63 relative to its parental varieties.

Parental variation in CHG methylation is associated with allelic-specific expression in elite hybrid rice.

Heterosis refers to the superior performance of hybrid lines over inbred parental lines. Besides genetic variation, epigenetic differences between parental lines are suggested to contribute to heterosis. However, the precise nature and extent of differences between the parental epigenomes and the reprograming in hybrids that govern heterotic gene expression remain unclear.