Identification of a new mechanism of histone methylation modification in response to drought stress

Identification of a new mechanism of histone methylation modification in response to drought stress

A new mechanism for histone methylation modification to regulate drought stress response was ascertained A new mechanism for histone methylation modification to regulate drought stress response was ascertained

Recently, Jin Jingbo, a researcher at the Institute of Botany, Chinese Academy of Sciences, explained the molecular mechanism of Arabidopsis JMJ27-mediated histone H3K9 demethylation that positively regulates the response of plants to drought stress
.

Related research results were published in "New Botanist"

Histone H3K9me2 modifications are mainly enriched in heterochromatin regions, which promote the silencing of transposons and other repetitive sequences
.

Interestingly, H3K9me2 modifications are also enriched in gene regions, and the induced expression of drought stress-responsive genes is associated with the decrease of H3K9me2 modification levels, but the molecular mechanism of H3K9me2 modification regulating plant drought stress response is still unclear

The researchers found that a mutant with a JmjC domain containing the protein JMJ27 has a drought-sensitive phenotype
.

Further research found that JMJ27 has histone H3K9 demethylase activity and positively regulates the response of plants to drought stress through its enzyme activity

After using RNA-seq analysis, the researchers identified the JMJ27 regulatory genes GOLS2 and RD20 (two positive regulators in response to drought stress)
.

Further research found that JMJ27 binds to the GOLS2 and RD20 genomes, and suppresses the silencing of these genes by reducing the H3K9me2 levels of these genes

In addition, the researchers also used proteomics and other methods to identify a subunit of the 26S proteasome, RPN1a, interacts with JMJ27 and negatively regulates the accumulation of JMJ27
.

Under drought stress conditions, the level of RPN1a protein decreased, leading to increased abundance of JMJ27 at GOLS2 and RD20 gene loci, thereby enhancing the transcriptional activation of these genes

These results indicate that the RPN1a-JMJ27 module finely regulates the level of H3K9me2, which is of great significance for plants to cope with harsh environmental conditions
.

(Source: Tian Ruiying, Chinese Science News)

Related paper information: https://doi.

https://doi.
org/10.
1111/nph.
17593