(Press-News.org)
A research team led by Prof. QIN Guozheng from the Institute of Botany of the Chinese Academy of Sciences has unveiled a previously unrecognized mechanism by which the RNA N6–methyladenosine (m6A) demethylase SlALKBH2 undergoes reduction-oxidation (redox) modification. This alteration affects its stability and its physiological role in regulating the normal ripening of tomato fruits.
In this study, published in Nature Plants, the researchers deepened their understanding of the role of hydrogen peroxide (H2O2), a mild oxidant that functions as a pivotal signaling molecule in controlling multiple biological processes. They found that H2O2-mediated oxidative modification regulates the function of SlALKBH2, which is essential for the proper ripening of fleshy fruits. This ripening stage represents the final phase of fruit development, directly influencing fruit quality and shelf life.
Specifically, the researchers showed how H2O2 signaling interacts with RNA methylation modification to regulate plant development in a coordinated way.
The most prevalent chemical modification in eukaryotic mRNAs is m6A methylation. It regulates various biological processes, including mRNA stability and translation efficiency, by modulating mRNA metabolism.
As members of the dioxygenase family, m6A demethylases, including SlALKBH2, are capable of oxidatively reversing m6A methylation. This capacity raises the question of whether SlALKBH2 itself is subject to oxidative modification, similar to other redox-sensitive proteins.
To test this hypothesis, the researchers transiently expressed the SlALKBH2 gene in Nicotiana benthamiana leaves treated with or without H2O2, then subsequently monitored the redox status of SlALKBH2.
The results indicated a marked sensitivity of SlALKBH2 to H2O2-induced oxidation, resulting in the formation of homodimers both in N. benthamiana leaves and in tomato fruits. Notably, exposure to H2O2 was shown to accelerate tomato fruit ripening, implicating SlALKBH2 oxidation in this process.
The formation of SlALKBH2 homodimers was attributed to the involvement of multiple cysteine (Cys) residues, with Cys39 identified as a crucial site; mutation at this location drastically reduced homodimer formation. While oxidative modification improved the stability of the SlALKBH2 protein, it did not affect its m6A demethylase activity.
Moreover, the researchers identified NADPH-thioredoxin reductase C (SlNTRC) as the interacting protein of SlALKBH2. They demonstrated that SlNTRC regulates the redox state of SlALKBH2, thus affecting its m6A demethylation function in tomatoes.
Stable SlNTRC knockout mutants were then generated in tomatoes using CRISPR–Cas9-mediated gene editing. The homozygous mutant line experienced substantial delays in vegetative growth and an inability to bear fruit.
This study established a connection between H2O2 signaling and m6A methylation, highlighting the significance of redox regulation of m6A modifiers in the control of fruit ripening.
Given the crucial role of RNA m6A methylation in various biological processes, researchers speculate that this regulatory mechanism may also play a role in other developmental processes.
In summary, this study not only enhances our understanding of the molecular mechanisms underlying fruit ripening, but also offers new insights and strategies for improving crop varieties.
END
T cells can independently prevent acute viral infections to an extent previously thought only possible with neutralising antibodies.
Findings challenge the longstanding reliance on neutralising antibodies for assessing viral immunity, and suggest that development of future vaccines must consider both antibody and T-cell responses for comprehensive protection.
Singapore, 10 January 2025—Scientists from Duke-NUS Medical School and the Singapore General Hospital have discovered that T cells—white blood cells that can destroy harmful pathogens—can completely prevent viral infection, to an extent ...
A new study based on the sampling and analysis of volcanic ash at Cumbre Vieja volcano in the Canary Islands, located off Africa’s northwest coast, suggests that the composition of magma could drive tremors during volcanic eruptions. The findings, which are detailed today in the journal Nature Geoscience in a paper led by scientists at the American Museum of Natural History and the City University of New York (CUNY), highlight the potential of volcanic ash analysis as a monitoring and forecasting tool.
“The volcano research community has gotten ...
A new study published in Advances in Atmospheric Sciences has found that ocean warming in 2024 has led to new record high temperatures. The ocean is the hottest it has ever been recorded by humans, not only at the surface temperature but also for the upper 2000 meters.
“The broken records in the ocean have become a broken record.” Said Prof. Lijing Cheng with the Institute of Atmospheric Physics at the Chinese Academy of Sciences. He led a team of 54 scientists from 7 countries and discussed how ...
In today’s world, telecommunications and global connectivity have witnessed an unprecedented increase, making intercultural communication an unavoidable reality. A concerning aspect of such communication is the element of cultural and linguistic diversity between people. However, there is very little consensus on whether cultural diversity truly matters in intercultural communications or if it simply promotes miscommunication.
“In academic literature, culture tends to be approached in a dichotomous stance, either through a lens of miscommunication or is considered an altogether irrelevant construct when it ...
A new analysis of U.S. mortality data reveals the disproportionate impact of traumatic brain injuries (TBI) on older adults, males and certain racial and ethnic groups.
The study, published in the peer-reviewed journal Brain Injury, provides a comprehensive analysis of TBI-related deaths across different population groups across the U.S. in 2021.
The findings indicate that suicides remain the most common cause of TBI-related deaths, followed by unintentional falls, and specific groups are disproportionately affected by these tragedies.
Men, in particular, were found to be most likely to die from a TBI – more than three times ...
Oral cancer is an increasingly prevalent disease worldwide, with over 300,000 new cases diagnosed each year. Among oral cancers, tongue cancer (TC) is the most common type and often carries a poor prognosis. Surgery combined with chemoradiotherapy is one of the main lines of treatment for high-risk cases of TC. However, recurrence rates are high since the tumors can reestablish themselves from only a few surviving cells. A few surviving cells are referred to as minimal residual disease (MRD).
Understanding the mechanisms behind MRD formation is paramount to improving treatment outcomes ...
With the intensification of global population aging, muscle atrophy, characterized by the loss of muscle mass and function, has become an important health issue affecting the elderly. Researchers have widely used various animal and cellular models to gain a deeper understanding of the pathophysiological mechanisms of muscle atrophy and develop effective treatment strategies (Figure 1). These models simulate human muscle atrophy through different induction methods, such as natural aging, gene editing, nutritional changes, physical activity, chronic wasting diseases, ...
Group Activity Recognition (GAR), which aims to identify activities performed collectively in videos, has gained significant attention recently. Existing GAR datasets typically annotate only a single Group Activity (GA) instance per sample, carefully selected from original videos. This approach, while precise, diverges significantly from real-world contexts, which often involve multiple GA instances. Moreover, single word-level annotations are insufficient to encapsulate the complex semantic information in GA, thereby constraining the expansion and ...
Researchers have developed a transfer learning-enhanced physics-informed neural network (TLE-PINN) for predicting melt pool morphology in selective laser melting (SLM). This novel approach combines physics-informed constraints with deep learning techniques, achieving superior accuracy, faster training times, and reduced computational demands. Published in Advanced Manufacturing, this breakthrough has significant potential to improve the efficiency of SLM processes, enable intelligent real-time process control, and enhance manufacturing quality.
Selective Laser Melting ...
In the quest to address contemporary health challenges and advance medical science, the concept of Holistic Integrative Medicine (HIM) emerges as a pivotal approach. This paradigm emphasizes the integration of medical knowledge and practices, advocating for a shift from traditional, fragmented medical models to a more comprehensive and human-centered system. HIM represents a conscious evolution in medical thought, aiming to align with the holistic needs of patients and the complex dynamics of health and disease. It underscores the importance of dimensionality reduction and differentiation as ...