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Cold is an important environmental factor limiting plant growth and development. Recent studies have revealed the complex regulatory networks associated with plant responses to cold and identified their interconnections with signaling pathways related to light, the circadian clock, plant hormones, and pathogen defense. In this article, we review recent advances in understanding the molecular basis of cold perception and signal transduction pathways. We also summarize recent developments in the study of cold-responsive growth and flowering. Finally, we propose future directions for the study of long-term cold sensing, RNA secondary structures in response to cold, and the development of cold-tolerant and high-yield crops. [ABSTRACT FROM AUTHOR]

Summary: Cold stress is a major abiotic stress that threatens maize (Zea mays L.) production worldwide. Understanding the molecular mechanisms underlying cold tolerance is crucial for breeding resilient maize varieties. Tonoplast intrinsic proteins (TIPs) are a subfamily of aquaporins in plants. Here, we report that TIP family proteins are involved in maize cold tolerance. The expression of most TIP genes was responsive to cold stress. Overexpressing TIP2;1, TIP3;2 or TIP4;3 reduced the cold tolerance of maize seedlings, while loss‐of‐function mutants of TIP4;3 exhibited enhanced cold tolerance. Candidate gene‐based association analysis revealed that a 328‐bp transposon insertion in the promoter region of TIP4;3 was strongly associated with maize cold tolerance. This transposon insertion conferred cold tolerance by repressing TIP4;3 expression through increased methylation of its promoter region. Moreover, TIP4;3 was found to suppress stomatal closure and facilitate reactive oxygen species (ROS) accumulation under cold stress, thereby inhibiting the expression of cold‐responsive genes, including DEHYDRATION‐RESPONSIVE ELEMENT BINDING FACTOR 1 (DREB1) genes and a subset of peroxidase genes, ultimately attenuating maize cold tolerance. This study thus elucidates the mechanism underlying TIP‐mediated cold tolerance and identifies a favourable TIP4;3 allele as a potential genetic resource for breeding cold‐tolerant maize varieties. [ABSTRACT FROM AUTHOR]

Understanding how maize (Zea mays) responds to cold stress is crucial for facilitating breeding programs of cold-tolerant varieties. Despite extensive utilization of the genome-wide association study (GWAS) approach for exploring favorable natural alleles associated with maize cold tolerance, few studies have successfully identified candidate genes that contribute to maize cold tolerance. In this study, we used a diverse panel of inbred maize lines collected from different germplasm sources to perform a GWAS on variations in the relative injured area of maize true leaves during cold stress—a trait very closely correlated with maize cold tolerance. We identified HSF21 , which encodes a B-class heat shock transcription factor (HSF) that positively regulates cold tolerance at both the seedling and germination stages. Natural variations in the promoter of the cold-tolerant HSF21 Hap1 allele led to increased HSF21 expression under cold stress by inhibiting binding of the basic leucine zipper bZIP68 transcription factor, a negative regulator of cold tolerance. By integrating transcriptome deep sequencing, DNA affinity purification sequencing, and targeted lipidomic analysis, we revealed the function of HSF21 in regulating lipid metabolism homeostasis to modulate cold tolerance in maize. In addition, we found that HSF21 confers maize cold tolerance without incurring yield penalties. Collectively, this study establishes HSF21 as a key regulator that enhances cold tolerance in maize, providing valuable genetic resources for breeding of cold-tolerant maize varieties. In this study, HSF21 , encoding a B-class heat shock transcription factor, was identified to be strongly associated with cold tolerance by GWAS using a panel of diverse maize inbred lines. Natural variations in the promoter of the cold-tolerant HSF21Hap1 allele cause increased HSF21 expression under cold stress due to attenuated binding with bZIP68, a negative regulator of cold tolerance. Multi-omics analyses further reveal that HSF21 is a crucial regulator of maize lipid metabolism under cold stress, thereby providing potential genetic targets for maize cold tolerance breeding. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a pressing concern in neurodegenerative research. To address the challenges in AD drug development, especially those targeting Aβ, this study uses deep learning and a pharmacological approach to elucidate the potential of pyrroloquinoline quinone (PQQ) as a neuroprotective agent for AD. Using deep learning for a comprehensive molecular dataset, blood–brain barrier (BBB) permeability is predicted and the anti‐inflammatory and antioxidative properties of compounds are evaluated. PQQ, identified in the Mediterranean‐DASH intervention for a diet that delays neurodegeneration, shows notable BBB permeability and low toxicity. In vivo tests conducted on an Aβ₁₋₄₂‐induced AD mouse model verify the effectiveness of PQQ in reducing cognitive deficits. PQQ modulates genes vital for synapse and anti‐neuronal death, reduces reactive oxygen species production, and influences the SIRT1 and CREB pathways, suggesting key molecular mechanisms underlying its neuroprotective effects. This study can serve as a basis for future studies on integrating deep learning with pharmacological research and drug discovery. [ABSTRACT FROM AUTHOR]

Cold stress is a major abiotic stress that adversely affects plant growth and crop productivity. The C‐REPEAT BINDING FACTOR/DRE BINDING FACTOR 1 (CBF/DREB1) transcriptional regulatory cascade plays a key role in regulating cold acclimation and freezing tolerance in Arabidopsis (Arabidopsis thaliana). Here, we show that max (more axillary growth) mutants deficient in strigolactone biosynthesis and signaling display hypersensitivity to freezing stress. Exogenous application of GR245DS, a strigolactone analog, enhances freezing tolerance in wild‐type plants and strigolactone‐deficient mutants and promotes the cold‐induced expression of CBF genes. Biochemical analysis showed that the transcription factor WRKY41 serves as a substrate for the F‐box E3 ligase MAX2. WRKY41 directly binds to the W‐box in the promoters of CBF genes and represses their expression, negatively regulating cold acclimation and freezing tolerance. MAX2 ubiquitinates WRKY41, thus marking it for cold‐induced degradation and thereby alleviating the repression of CBF expression. In addition, SL‐mediated degradation of SMXLs also contributes to enhanced plant freezing tolerance by promoting anthocyanin biosynthesis. Taken together, our study reveals the molecular mechanism underlying strigolactones promote the cold stress response in Arabidopsis. Synopsis: Plants respond to extreme cold stress by synthesizing strigolactones; however, how this class of plant hormones promotes freezing tolerance is still poorly understood. Here, cold‐induced strigolactones are shown to promote plant survival in sub‐zero temperatures by enhancing expression of freezing tolerance regulators DREB1/CBF.Strigolactones positively regulate plant freezing tolerance via a CBF‐dependent pathway.The E3 ligase MAX2 interacts with and ubiquitinates the transcription factor WRKY41, mediating its cold‐induced degradation.WRKY41 represses the cold‐induced expression of CBFs by directly binding to their promoters.SLs‐mediated degradation of SMXLs also contributes to enhanced freezing tolerance by accumulating anthocyanin. [ABSTRACT FROM AUTHOR]