Seed longevity is one of the most essential characteristics of seed quality. Two chromosome segment substitution lines, I178 and X178, which show significant differences in seed longevity, were subjected to transcriptome sequencing before and after five days of accelerated aging (AA) treatments. Compared to the non-aging treatment, 286 and 220 differentially expressed genes (DEGs) were identified after 5 days of aging treatment in I178 and X178, respectively. Of these DEGs, 98 were detected in both I178 and X178, which were enriched in Gene Ontology (GO) terms of the cellular component of the nuclear part, intracellular part, organelle and membrane. Only 86 commonly downregulated genes were enriched in GO terms of the carbohydrate derivative catabolic process. Additionally, transcriptome analysis of alternative splicing (AS) events in I178 and X178 showed that 63.6% of transcript isoforms occurred AS in all samples, and only 1.6% of transcript isoforms contained 169 genes that exhibited aging-specific AS arising after aging treatment. Combined with the reported QTL mapping result, 7 DEGs exhibited AS after aging treatment, and 13 DEGs in mapping interval were potential candidates that were directly or indirectly related to seed longevity.

Pentatricopeptide repeat (PPR) proteins involved in mitochondrial RNA cytidines (C) to uridines (U) editing mostly result in the stagnant embryo and endosperm development when losing function. However, less is known about PPR that involved in farinaceous endosperm formation and maize quality. Here, we cloned a maize DYW-type PPR Defective Kernel605 (Dek605). Mutation of Dek605 delayed seed and seedling development. Mitochondrial transcript analysis of dek605 revealed that loss of DEK605 impaired C-to-U editing at the nad1-608 site and fails to alter Ser203 to Phe203 in NAD1 (dehydrogenase complex I), disrupting complex I assembly and reducing NADH dehydrogenase activity. Meanwhile, complex III and IV in the cytochrome pathway, as well as AOX2 in the alternative respiratory pathway, are dramatically increased. Interestingly, the mutation resulted in opaque endosperm and increased levels of the free amino acids ALA, ASP and PHE in dek605. The down- and up-regulated genes were mainly involving in stress response-related and seed dormancy-related pathways, respectively, were observed after transcriptome analysis of dek605 at 12 day after pollination (DAP). Collectively, these results indicate that Dek605 specifically affects the single nad1-608 site and is required for normal seed development and resulted in nutritional quality relevant amino acid accumulation.

Anthocyanins are a class of antioxidants that scavenge free radicals in cells and play an important role in promoting human health and preventing many diseases. Here, we characterized a maize Bronze gene (BZ1) from the purple colored W22 introgression line, which encodes an anthocyanin 3-O-glucosyltransferase, a key enzyme in the anthocyanin synthesis pathway. Mutation of ZmBZ1 showed bronze-colored seeds and reduced anthocyanins in seeds aleurone layer, seedlings coleoptile, and stem of mature plants by comparison with purple colored W22 (WT). Furthermore, we proved that maize BZ1 is an aleurone layer-specific expressed protein and sub-located in cell nucleus. Real-time tracing of the anthocyanins in developing seeds demonstrated that the pigment was visible from 16 DAP (day after pollination) in field condition, and first deposited in the crown part then spread all over the seed. Additionally, it was transferred along with the embryo cell activity during seed germination, from aleurone layer to cotyledon and coleoptile, as confirmed by microscopy and real-time qRT-PCR. Finally, we demonstrated that the ZmBZ1 contributes to stress tolerance, especially salinity. Further study proved that ZmBZ1 participates in reactive oxygen scavenging (ROS) by accumulating anthocyanins, thereby enhancing the tolerance to abiotic stress.

Hypertrophic scar (HS) is a chronic inflammatory skin disease characterized by excessive deposition of extracellular matrix, but the exact mechanisms related to its formation remain unclear, making it difficult to treat. This study aimed to investigate the potential role of cuproptosis in the information of HS. To this end, we used single-cell sequencing and bulk transcriptome data, and screened for cuproptosis-related genes (CRGs) using differential gene analysis and machine learning algorithms (random forest and support vector machine). Through this process, we identified a group of genes, including ATP7A, ULK1, and MTF1, as novel therapeutic targets for HS. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to confirm the mRNA expression of ATP7A, ULK1, and MTF1 in both HS and normal skin (NS) tissues. We also constructed a diagnostic model for HS and analyzed the immune infiltration characteristics. Additionally, we used the expression profiles of CRGs to perform subgroup analysis of HS. We focused mainly on fibroblasts in the transcriptional profile at single-cell resolution. By calculating the cuproptosis activity of each fibroblast, we found that cuproptosis activity of normal skin fibroblasts increased, providing further insights into the pathogenesis of HS. We also analyzed the cell communication network and transcription factor regulatory network activity, and found the existence of a fibroblast-centered communication regulation network in HS, where cuproptosis activity in fibroblasts affects intercellular communication. Using transcription factor regulatory activity network analysis, we obtained highly active transcription factors, and correlation analysis with CRGs suggested that CRGs may serve as potential target genes for transcription factors. Overall, our study provides new insights into the pathophysiological mechanisms of HS, which may inspire new ideas for the diagnosis and treatment.