RESUMO
Background: Imbalances between Bcl-2 and caspase-3 are significant evidence of apoptosis, which is considered an influential factor in rapidly occurring neuronal cell death and the decline of neurological function after stroke. Studies have shown that acupuncture can reduce poststroke brain cell damage via either an increase in Bcl-2 or a reduction in caspase-3 exposure. The current study aimed to investigate whether acupuncture could modulate Bcl-2 and caspase-3 expression through histone acetylation modifications, which could potentially serve as a neuroprotective mechanism. Methods: This study used TTC staining, Nissl staining, Clark neurological system score, and Evans Blue (EB) extravasation to evaluate neurological damage following stroke. The expression of Bcl-2/caspase-3 mRNA was detected by real-time fluorescence quantification of PCR (real-time PCR), whereas the protein expression levels of Bcl-2, Bax, caspase-3, and cleaved caspase-3 were assessed using western blotting. TUNEL staining of the ischemic cortical neurons determined apoptosis in the ischemic cortex. Histone acetyltransferase (HAT) and histone deacetylase (HDAC) activities, along with the protein performance of AceH3, H3K9ace, and H3K27ace, were detected to evaluate the degree of histone acetylation. The acetylation enrichment levels of H3K9 and K3K27 in the Bcl-2/caspase-3 gene were assessed using Chromatin Immunoprecipitation (ChIP) assay. Results: Our data demonstrated that electroacupuncture (EA) exerts a significant neuroprotective effect in middle cerebral artery occlusion (MCAO) rats, as evidenced by a reduction in infarct volume, neuronal damage, Blood-Brain Barrier (BBB) disruption, and decreased apoptosis of ischemic cortical neurons. EA treatment can promote the mRNA and protein expression of the Bcl-2 gene in the ischemic brain while reducing the mRNA and protein expression levels of caspase-3 and effectively decreasing the protein expression levels of Bax and cleaved caspase-3. More importantly, EA treatment enhanced the level of histone acetylation, including Ace-H3, H3K9ace, and H3K27ace, significantly enhanced the occupancy of H3K9ace/H3K27ace at the Bcl-2 promoter, and reduced the enrichment of H3K9ace and H3K27ace at the caspase-3 promoter. However, the Histone Acetyltransferase inhibitor (HATi) treatment reversed these effects. Conclusions: Our data demonstrated that EA mediated the expression levels of Bcl-2 and caspase-3 in MCAO rats by regulating the occupancy of acetylated H3K9/H3K27 at the promoters of these two genes, thus exerting a cerebral protective effect in ischemic reperfusion (I/R) injury.
RESUMO
Engineering disease-resistant plants can be a powerful solution to the issue of food security. However, it requires addressing two fundamental questions: what genes to express and how to control their expressions. To find a solution, we screen CRISPR-edited upstream open reading frame (uORF) variants in rice, aiming to optimize translational control of disease-related genes. By switching uORF types of the 5'-leader from Arabidopsis TBF1, we modulate the ribosome accessibility to the downstream firefly luciferase. We assume that by switching uORF types using CRISPR, we could generate uORF variants with alternative translation efficiency (CRISPR-aTrE-uORF). These variants, capable of boosting translation for resistance-associated genes and dampening it for susceptible ones, can help pinpoint previously unidentified genes with optimal expression levels. To test the assumption, we screened edited uORF variants and found that enhanced translational suppression of the plastic glutamine synthetase 2 can provide broad-spectrum disease resistance in rice with minimal fitness costs. This strategy, which involves modifying uORFs from none to some, or from some to none or different ones, demonstrates how translational agriculture can speed up the development of disease-resistant crops. This is vital for tackling the food security challenges we face due to growing populations and changing climates.
Assuntos
Sistemas CRISPR-Cas , Resistência à Doença , Fases de Leitura Aberta , Oryza , Oryza/genética , Resistência à Doença/genética , Fases de Leitura Aberta/genética , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Doenças das Plantas/genética , Arabidopsis/genética , Plantas Geneticamente Modificadas/genética , Biossíntese de Proteínas/genética , Regulação da Expressão Gênica de Plantas , Produtos Agrícolas/genética , Traduções , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genéticaRESUMO
Disease tolerance is an essential defense strategy against pathogens, alleviating tissue damage regardless of pathogen multiplication. However, its genetic and molecular basis remains largely unknown. Here, we discovered that protein condensation at the endoplasmic reticulum (ER) regulates disease tolerance in Arabidopsis against Pseudomonas syringae. During infection, Hematopoietic protein-1 (HEM1) and Bax-inhibitor 1 (BI-1) coalesce into ER-associated condensates facilitated by their phase-separation behaviors. While BI-1 aids in clearing these condensates via autophagy, it also sequesters lipid-metabolic enzymes within condensates, likely disturbing lipid homeostasis. Consequently, mutations in hem1, which hinder condensate formation, or in bi-1, which prevent enzyme entrapment, enhance tissue-damage resilience, and preserve overall plant health during infection. These findings suggest that the ER is a crucial hub for maintaining cellular homeostasis and establishing disease tolerance. They also highlight the potential of engineering disease tolerance as a defense strategy to complement established resistance mechanisms in combating plant diseases.