Pu Zhao

YABBY transcription factors (TFs) are key regulators involved in diverse aspects of plant growth, organogenesis, and adaptation to environmental stresses. However, the functional characteristics of YABBY TFs in maize remain largely unexplored. In this study, we systematically identified 12 YABBY genes in the maize genome and characterized their gene structures, physicochemical properties, chromosome location, and genomic collinearity. Phylogenetic analysis classified these genes into five subfamilies, with members of each subfamily exhibiting highly conserved exon–intron structures and motif compositions, indicative of potential functional conservation within subfamilies. Cis-regulatory element analysis indicated that YABBY genes may be involved in developmental processes, abiotic stress responses, and light-mediated signaling pathways. Moreover, transcriptome sequencing combined with qRT-PCR validation demonstrated that several YABBY genes, including ZmYABBY2, ZmYABBY5, ZmYABBY8, and ZmYABBY9, are responsive to low-phosphorus and high-nitrogen conditions, implying their potential roles in nutrient stress adaptation. It is worth mentioning that this study redefined the composition of the maize YABBY gene family by excluding a previously annotated member and, for the first time, established a link between YABBY transcription factors and nutrient stress responses. Meanwhile, this is also the first time that protein structure analysis, cis-regulatory element analysis, interspecific collinearity analysis and subcellular localization have been performed on maize ZmYABBY gene family. In summary, our study provides valuable gene resources for maize molecular breeding and offers new insights into the functions of YABBY TFs.

Background: High temperatures during the early generative stage significantly threaten maize productivity, yet the molecular basis of heat tolerance remains unclear. Methods: To elucidate the molecular mechanisms of heat tolerance in maize, two hybrids—ZD309 (heat-tolerant) and XY335 (heat-sensitive)—were selected for integrated transcriptomic and physiological analyses. The plants were subjected to high-temperature treatments (3–5 °C above ambient field temperature) for 0, 1, 3, 5, and 7 days, with controls grown under natural conditions. Physiological indices, including Superoxide dismutase (SOD) activity, and proline (PRO), malondialdehyde (MDA), soluble sugar, and protein content, were measured. Results: Transcriptome analysis identified 1595 differentially expressed genes (DEGs) in XY335 (509 up- and 1086 down-regulated) and 1526 DEGs in ZD309 (863 up- and 663 down-regulated), with the most pronounced changes occurring on day 5. Key DEGs in XY335 were enriched in galactose metabolism and carbohydrate catabolism, whereas ZD309 exhibited rapid activation of oxidative stress and cell wall integrity pathways. Mfuzz time-series analysis categorized DEGs from XY335 and ZD309 into six clusters each. Weighted gene co-expression network analysis (WGCNA) identified 10 hub genes involved in ubiquitin thioesterase activity and RNA modification, suggesting protein-level regulatory roles. Conclusions: This study reveals distinct transcriptional dynamics between heat-tolerant and heat-sensitive varieties, providing candidate genes for breeding thermotolerant maize and advancing our understanding of heat stress responses during critical reproductive stages.

Light is a vital environmental cue that profoundly influences the development of plants. LED lighting offers significant advantages in controlled growth environments over fluorescent lighting. Under monochromatic blue LED light, wheat plants exhibited reduced stature, accelerated spike development, and a shortened flowering period with increased blue light intensity promoting an earlier heading date. In this study, we conducted a comprehensive transcriptome analysis to investigate the molecular mechanisms underlying wheat plants’ response to varying light conditions. We identified 34 types of transcription factors (TFs) and highlighted the dynamic changes of key families such as WRKY, AP2/ERF, MYB, bHLH, and NAC, which play crucial roles in light-induced gene regulation. Additionally, this study revealed differential effects of blue and red light on the expression levels of genes related to hormones such as cytokinin (CK) and salicylic acid (SA) synthesis as well as significant changes in pathways such as flavonoid biosynthesis, circadian rhythms, chlorophyll synthesis, and flowering. Particularly, blue light upregulated genes involved in chlorophyll synthesis, contrasting with the downregulation observed under red light. Furthermore, blue light enhanced the expression of anthocyanin synthesis-related genes, such as CHS, underscoring its role in promoting anthocyanin accumulation. These findings provide valuable insights into how light quality impacts crop growth and development.

Nitrogen (N), as the main component of biological macromolecules, maintains the basic process of plant growth and development. GOGAT, as a key enzyme in the N assimilation process, catalyzes α-ketoglutaric acid and glutamine to form glutamate. In this study, six GOGAT genes in wheat (Triticum aestivum L.) were identified and classified into two subfamilies, Fd-GOGAT (TaGOGAT2s) and NADH-GOGAT (TaGOGAT3s), according to the type of electron donor. Subcellular localization prediction showed that TaGOGAT3-D was localized in mitochondria and that the other five TaGOGATs were localized in chloroplasts. Via the analysis of promoter elements, many binding sites related to growth and development, hormone regulation and plant stress resistance regulations were found on the TaGOGAT promoters. The tissue-specificity expression analysis showed that TaGOGAT2s were mainly expressed in wheat leaves and flag leaves, while TaGOGAT3s were highly expressed in roots and leaves. The expression level of TaGOGATs and the enzyme activity of TaGOGAT3s in the leaves and roots of wheat seedlings were influenced by the treatment of N deficiency. This study conducted a systematic analysis of wheat GOGAT genes, providing a theoretical basis not only for the functional analysis of TaGOGATs, but also for the study of wheat nitrogen use efficiency (NUE).

High temperature around flowering has a serious impact on the growth and development of maize. However, few maize genes related to flowering under heat stress have been confirmed, and the regulatory mechanism is unclear. To reveal the molecular mechanism of heat tolerance in maize, two maize hybrids, ZD309 and XY335, with different heat resistance, were selected to perform transcriptome and metabolomics analysis at the flowering stage under heat stress. In ZD309, 314 up-regulated and 463 down-regulated differentially expressed genes (DEGs) were detected, while 168 up-regulated and 119 down-regulated DEGs were identified in XY335. By comparing the differential gene expression patterns of ZD309 and XY335, we found the “frontloaded” genes which were less up-regulated in heat-tolerant maize during high temperature stress. They included heat tolerance genes, which may react faster at the protein level to provide resilience to instantaneous heat stress. A total of 1062 metabolites were identified via metabolomics analysis. Lipids, saccharides, and flavonoids were found to be differentially expressed under heat stress, indicating these metabolites’ response to high temperature. Our study will contribute to the identification of heat tolerance genes in maize, therefore contributing to the breeding of heat-tolerant maize varieties.