In eukaryotic organisms, histone methylation modifications play a crucial role in regulating chromatin structure, gene transcription, and other chromatin-related processes. The demethylases (JMJs) containing the Jumonji C (JmjC) domain dynamically control the levels of histone methylation; however, the universal mechanisms of JMJ activity control remain unclear.

On July 14, 2023, Professors Yuehui He and Xiao Luo of the Peking University Institute of Advanced Agricultural Sciences published a research article in Science titled "Control of histone demethylation by nuclear-localized α-ketoglutarate dehydrogenase" (https://www.science.org/doi/10.1126/science.adf8822). The article reports on the rate-limiting enzyme of the tricarboxylic acid cycle (TCA Cycle), α-ketoglutarate dehydrogenase complex (KGDH), which responds to light signals entering the cell nucleus and interacts with JMJs protein. KGDH, by competitively metabolizing α-ketoglutarate, suppresses the histone demethylation activity of JMJs, thereby controlling the methylation modifications of histones at the level of the whole genome and consequently regulating the molecular mechanisms of the expression of a series of environmentally responsive genes.

 

 

On July 12, 2023, professors Yuehui He and Xiao Luo published a paper in Nature titled "Cold induction of nuclear FRIGIDA condensation in Arabidopsis" (https://www.nature.com/articles/s41586-023-06189-z). By employing the CRISPR/Cas9 method to delete the promoter region of the antisense long noncoding RNA (lncRNA) COOLAIR at the FLC locus, a gene suppressing flowering, they generated two strains in which COOLAIR is not expressed under either normal or cold conditions. After introducing functional FRI-GFP fusion protein into these two strains, they confirmed that cold temperatures induce the formation of FRI protein condensates. Nevertheless, they found that the absence of COOLAIR expression had no effect on the formation of these FRI condensates. Further research revealed that the lack of COOLAIR expression also did not impact the silencing of FLC under persistent and stable cold conditions. In conclusion, the role of COOLAIR in the process of silencing FLC expression under sustained cold conditions (vernalization) still necessitates further study.