Search Results (114)

Flowering is a key agronomic trait that directly influences the yield of the tea-oil tree (Camellia oleifera). Floral initiation, which precedes flower bud differentiation, represents a critical developmental stage affecting the flowering outcomes. However, the molecular mechanisms underlying floral initiation in C. oleifera remain poorly understood. In this study, buds from five key developmental stages of a 12-year-old C. oleifera cultivar ‘changlin53’ were collected as experimental samples. Scanning electron microscopy was employed to identify the stage of floral initiation. UPLC-MS/MS was used to analyze endogenous gibberellin (GA) concentrations, while transcriptomic analysis was performed to reveal the underlying transcriptional regulatory network. Six GA types were detected during floral initiation and petal development. GA₄ was exclusively detected at the sprouting stage (BII), while GA₃ was present in all samples but was significantly lower in BII and the flower bud primordium formation stage (BIII) than in the other samples. A total of 64 differentially expressed genes were concurrently enriched in flower development, reproductive shoot system development, and shoot system development. Weighted gene co-expression network analysis (WGCNA) identified eight specific modules significantly associated with different developmental stages. The magenta module, containing Unigene0084708 (CoFT) and Unigene0037067 (CoLEAFY), emerged as a key regulatory module driving floral initiation. Additionally, GA20OX1 and GA2OX8 were identified as candidate genes involved in GA-mediated regulation of floral initiation. Based on morphological and transcriptomic analyses, we conclude that floral initiation of C. oleifera is a continuous regulatory process governed by multiple genes, with the FT-LFY module playing a central role in the transition from apical meristem to floral meristem. Full article

Maize (Zea mays L.) is one of the most important staple food crops globally. One-third of global maize production is located in areas with high or extreme water scarcity and concurrently faces the challenge of low nitrogen use efficiency. Therefore, achieving synergistically high-efficiency water and nitrogen utilization in maize production is of great significance for agricultural sustainable development and global food security. In recent years, more articles have focused on the physiological mechanisms and management practices of efficient water and nitrogen utilization in maize. Unfortunately, there is a relative scarcity of research on the interactive effects between water and nitrogen on the development of young ears, which plays a crucial role in maize productivity. By compiling the most pertinent publications, this review endeavors to consolidate the existing knowledge on the interactive effects between water and nitrogen on maize production. Moreover, it advances potential physiological mechanisms and strategies for high-efficiency water and nitrogen utilization in terms of root system functioning, phytohormones, metabolism, and organ development. The changes in the availability of water and nitrogen have a significant impact on the development of young ears during the critical period, which in turn directly determines the grain number per ear and grain weight. Full article

Auxins play a critical role in establishing the embryo axis and embryonic pattern. Our study aimed to determine the developmental stage of 21-day old oat (Avena sativa L.) haploid embryos, obtained by distant crossing with maize, and examined oat zygotic embryos at different developmental stages for their levels of endogenous indole-3-acetic acid (IAA), its metabolites, and IAA localization. The content of auxin metabolites was determined by HPLC-MS/MS, while IAA visualization in embryos was performed by immunohistochemistry and observed under confocal microscopy. We found that 21-day-old haploid embryos contained half the IAA concentration of age-matched zygotic embryos. Simultaneously, the total conjugated auxins (IAA-Asp, IAA-Glu, meIAA) were higher than in zygotic embryos, regardless of their age. Immunolocalization revealed IAA accumulation in embryos aligned with regions of tissue differentiation (e.g., shoot apical meristem, radicle primordium, and coleptile). We conclude that limited morphogenetic progression, evidenced by microscopic sections accompanied by changes in IAA content and distribution in haploid embryos, indicates a developmental stage earlier than the coleoptilar stage of zygotic embryos which occurs 9 days after pollination. Our findings may be useful in embryo rescue techniques, suggesting modulation of auxin concentration in in vitro culture. Full article

To investigate the correlation between soil fungal communities and the growth and development of Morchella sextelata, this study utilized high-throughput sequencing technology to analyze the structure and diversity of soil fungal communities at various growth stages of Morchella sextelata. The results revealed significant variations in the diversity, composition, and relative abundance of soil fungal communities across different growth stages of Morchella sextelata, demonstrating stage-specific characteristics. Alpha diversity analysis indicated that the Shannon index was highest during the CK stage, significantly decreased in the LS stage (p < 0.01), increased again in the LY stage, and then declined once more in the LC stage. Beta diversity analysis (Principal Coordinates Analysis, PCoA) demonstrated significant differences in fungal community structure across various stages (R = 0.9567, p = 0.001). At the phylum level, Ascomycota remained dominant throughout all growth stages of Morchella sextelata, but its relative abundance exhibited significant dynamic changes. At the fungal genus level, Paecilomyces dominated in the primordium stage (27.12%), whereas Morchella dominated in the conidial stage (LS) and fruiting body stage (LC), accounting for 43.48% and 41.61%, respectively. Additionally, in the LC stage, the plant pathogenic genus Fusarium significantly increased (3.49%), indicating an elevated risk of disease. Functional prediction results revealed that saprotrophic fungi were predominant at all stages, but the relative abundance of pathogenic fungi gradually increased, rising from 0.06% in the LS stage to 41.41% in the LC stage, a substantial increase of 40.81% compared to the LS stage. This suggests a higher potential risk of disease occurrence during the fruiting body stage. Our study provides an overview of the dynamics of soil fungal communities during the cultivation of Morchella sextelata. These findings offer scientific insights for optimizing the artificial cultivation technology of Morchella sextelata and provide a reference for disease prevention and control. Full article

Cinnamomum bodinieri is a tree species highly valued for its superior-quality timber and ecological benefits. However, its large-scale propagation is hindered by the low efficiency of adventitious root (AR) formation. This study investigated the physiological and molecular mechanisms underlying AR formation in C. bodinieri. The results revealed that ARs originate from callus tissue, with the root primordium classified as a latent type. During AR formation, concentrations of soluble protein and soluble sugar decreased, while the activities of superoxide dismutase (SOD), peroxidase (POD), and indole-3-acetic acid oxidase (IAAO) peaked 20 days after cutting (CB2), with polyphenol oxidase (PPO) activity exhibiting an “N”-shaped trend. These findings indicate that substantial nutrient consumption is required for AR formation, with SOD, POD, PPO, and IAAO positively regulating the process. Indole-3-acetic acid (IAA) levels significantly decreased during the early stages of cutting but increased thereafter, whereas the concentration of abscisic acid (ABA) continuously rose. Similar trends were observed for zeatin riboside (ZR) and gibberellic acid (GA). Transcriptome analysis identified 28 key genes involved in plant hormone signal transduction pathways. Furthermore, weighted gene co-expression network analysis (WGCNA) pinpointed 14 hub genes, including CYP94B3 and NAC82, linked to hormone-associated traits. Furthermore, quantitative real-time PCR (qRT-PCR) confirmed the accuracy of the transcriptome sequencing results. This analysis uncovered critical interactions between hormonal signaling pathways and pivotal gene networks. Overall, the findings highlight the central regulatory role of endogenous hormones in AR formation, with IAA serving as the predominant regulator. Full article

The double-flowering phenotype is crucial for improving the ornamental value of flowering plants; this trait substantially enhances the varieties of Syringa vulgaris L. To date, no studies have examined the transcriptomics and metabolomics of key nodes in the flower bud differentiation of the single and double flowers of Syringa. This study investigated both the single and double flowers of S. vulgaris using a comprehensive, multifaceted analytical approach, including physiological assessments, transcriptomics, and metabolomics. The floral bud differentiation process can be divided into six distinct stages. Compared with the single flowers, the double flowers of S. vulgaris presented significant developmental delays during floral bud differentiation. Although there was no significant difference in the soluble protein content between the two flower types during this process, the soluble sugar content varied during pistil primordium differentiation and as temperature increased. The antioxidant enzyme activity was significantly greater in the double flowers than in the single flowers during most differentiation stages, while the malondialdehyde (MDA) level gradually increased. The levels of endogenous hormones, such as indole-3-acetic acid (IAA), gibberellin (GA₃), and abscisic acid (ABA), differed between the two flower types. The transcriptomics and metabolomics results indicated that during pistil primordium differentiation and subsequent development, the double flowers exhibited increased antioxidant enzyme activity and secondary metabolite accumulation. These secondary metabolites not only contributed to the vibrant coloration of the double flowers but also increased their cellular metabolic stability and stress tolerance through their antioxidant properties. Conversely, the rapid differentiation mechanism of the single flowers of S. vulgaris relied more on efficient primary metabolism to meet simpler structural demands. These findings not only provide scientific guidance for S. vulgaris breeding programs but also expand its potential in horticultural and landscape applications, offering a new theoretical foundation for studies on floral organ development in Oleaceae species. Full article

Chinese bayberry (Myrica rubra or Morella rubra) is a valuable fruit, yet the mechanism of its flesh segment development is not well understood. Using paraffin sectioning, we investigated the flower buds of the ‘Biqi’ and ‘Zaojia’ varieties, revealing that the flesh segment development in these Chinese bayberry varieties involved the formation of a primordium outside the ovary wall, the establishment of a simple columnar structure, and the formation of the primary flesh segment. Assessment of endogenous hormone levels indicated the significant reductions in jasmonic acid (JA) and indole-3-acetic acid (IAA) levels at the critical stages of flesh segment development. Correlation analysis highlighted the essential roles of IAA, JA, abscisic acid (ABA), and gibberellins in the flesh segment developmental process, underscoring the complex interactions driven primarily by the IAA, JA, and ABA networks. Gene modules positively correlated with flesh segment development were identified using transcriptome-based weighted gene co-expression network analysis (WGCNA). Differentially expressed genes (DEGs) were enriched in plant hormone signal transduction pathways, particularly for upregulated genes associated with auxin and JA signaling. Key genes predicted to be involved in flesh segment development included LAX2 and LAX3 (auxin transport), JAZ6 (JA signaling repression), and KAN1 and KAN4 (regulating multiple hormonal signaling pathways). Quantitative real-time polymerase chain reaction (qRT-PCR) validation confirmed that the expression trends for these genes were consistent across both varieties, particularly for CRC, SEP1, SEP3, IAA7, and JAZ6. Immunofluorescence localization studies revealed that auxin was primarily distributed in the central vascular bundle and outer cells of the flesh segment. This uneven auxin distribution might contribute to the unique morphology of flesh segments. Overall, this study provides insights into the hormonal regulation and genetic factors involved in the development of Chinese bayberry flesh segments. Full article

Rose is one of the most popular ornamental plants worldwide. The double-flower trait, referring to flowers with extra petals, has been a key focus in rose breeding history. However, the genetic mechanisms regulating petal number in roses are still not fully understood. Here, we identified the CUP-SHAPED COTYLEDON 3 (RhCUC3) gene in the miniature rose (Rosa hybrida ‘Eclair’). The expression of RhCUC3 was high during the petal and stamen primordium differentiation stages but declined sharply during pistil primordium development. RhCUC3 belongs to the NAM/CUC3 subgroup of NAC transcription factors and is localized in the nucleus. The transcript level of RhCUC3 increased significantly with ABA and GA treatments and was inversely down-regulated with MeJA and 6-BA treatments. Silencing RhCUC3 using virus-induced gene silencing (VIGS) in rose ‘Eclair’ significantly decreased the number of petaloid stamens and normal petals while slightly increasing the number of stamens. Additionally, the expression of RhAG and RhAGL, two MADS-box genes associated with floral organ identity, was significantly higher in TRV-RhCUC3 compared to the TRV control. These findings suggest that RhCUC3 enhances stamen petaloidy and petal number, potentially by modulating the expression of RhAG and RhAGL, providing new insights into the function of NAC transcription factors in plants. Full article

The eye primordium of vertebrates initially forms exactly at the side of the head. Later, the eyeball architecture is tuned to see ahead with better visual acuity, but its molecular basis is unknown. The position of both eyes in the face alters in patients with holoprosencephaly due to Sonic hedgehog (Shh) mutations that disturb the development of the ventral midline of the neural tube. However, patient phenotypes vary extensively, and microforms without a brain anomaly relate instead to alternation of gene expression of the Shh signaling center in the facial primordia. We identified novel missense mutations of the Shh gene in two patients with a dislocated fovea, where the photoreceptor cells are condensed. Functional assays showed that Shh upregulates Patched and Gli and downregulates Pax6, and that Shh mutations alter these activities. Gain of function of Shh in a chick embryo retards retinal development and eyeball growth depending on the location of Shh expression, while loss of function of Shh promotes these features. We postulate that a signaling molecule like Shh that emanates from the face controls the extent of differentiation of the neural retina in a position-specific manner and that this may result in the formation of the fovea at the correct location. Full article

Periodic mycelial subculture is a method commonly used for the storage of edible mushrooms, but excessive subculturing can lead to the degeneration of strains. In this study, the Volvariella volvacea strain V971(M0) was successively subcultured on PDA medium every 4 days, and one generation of strains was preserved every 4 months. Thus, five generations of subcultured strains (M1–M5) were obtained after 20 months of mycelial subculturing, their production traits were determined, and transcriptomic analysis was performed using RNA-seq; the differentially expressed genes were verified via RT-qPCR. The results showed that as the number of subcultures increased, the diameter of the mycelium and biological efficiency gradually decreased; in addition, the time in which the primordium formed increased and the production cycle was lengthened, while strains M4 and M5 lacked the ability to produce fruiting bodies. There were 245 differentially expressed genes between the M1–M5 and M0 strains, while the highest number of differentially expressed genes was between M3 and M0, at 1439; the smallest number of differentially expressed genes was between M2 and M0, at 959. GO enrichment analysis showed that the differentially expressed genes were mainly enriched in metabolic processes, organelle components, and catalytic activities. KEGG enrichment analysis showed that the differentially expressed genes were mainly enriched in metabolic pathways. The further annotation of differentially expressed genes showed that 39, 24, and 24 differentially expressed genes were related to substrate degradation, amino acid synthesis and metabolism, and reactive oxygen species metabolism, respectively. The downregulation of the related differentially expressed genes would lead to the excessive accumulation of reactive oxygen species, inhibit nutrient absorption and energy acquisition, and lead to the degradation of V. volvacea. These findings could form a theoretical basis for the degeneration mechanism of V. volvacea, and also provide a basis for the molecular function study of the genes related to strain degradation. Full article

Adventitious root (AR) formation in plants originates from non-root organs such as leaves and hypocotyls. Auxin signaling is essential for AR formation, but the roles of other phytohormones are less clear. In Arabidopsis, at least two distinct mechanisms can produce ARs, either from hypocotyls as part of the general root architecture or from wounded organs during de novo root regeneration (DNRR). In previous reports, gibberellin acid (GA) appeared to play reverse roles in both types of ARs, since GA treatment blocks etiolation-induced AR formation from hypocotyls, whereas GA synthesis and signaling mutants apparently displayed reduced DNRR from detached leaves. In order to clarify this contradiction, we employed the GA biosynthesis inhibitor paclobutrazol (PBZ) and found that PBZ had positive effects on both types of AR formation in Arabidopsis. Consistently, GA treatment had negative effects on both AR formation mechanisms, while loss of GA synthesis and signaling promoted DNRR under our conditions. Our results show that PBZ treatment can rescue declined AR formation in difficult-to-root leaf explants such as erecta receptor mutants. Furthermore, transcriptional profiling revealed that PBZ treatment altered GA, brassinosteroids, and auxin responses, which included the up-regulation of LBD16 that is well known for its pivotal role in AR initiation. Full article

Pleurotus tuoliensis is a precious edible mushroom with a long cultivation cycle. Despite being cultivated in China for nearly 30 years, research on the molecular mechanisms underlying its primordium formation remains limited. In this study, the molecular mechanisms by which incubation time affects the primordium formation of P. tuoliensis were investigated using RNA-seq technology and lipid content detection. Our research revealed that the transcription of genes involved in lipid metabolism and lipid levels changed significantly during different incubation periods. Distinct differences were observed in gene transcription associated with signaling pathways, sphingolipid metabolism, fatty acid metabolism, and steroid biosynthesis in mycelia cultured for varying days and then stimulated by low temperature and light. These findings indicate that lipid accumulation and alterations in mycelial cell membrane components during incubation may affect the mycelial response to environmental signals, subsequently regulating primordium formation. This study revealed the crucial role of lipid metabolism during incubation in the primordium formation of P. tuoliensis, providing a novel perspective for investigating the molecular mechanism underlying fruiting body development. Full article

In recent years, the increasing global demand for mushrooms has made the enhancement of mushroom yield a focal point of research. Currently, the primary methods for developing high-yield mushroom varieties include mutation- and hybridization-based breeding. However, due to the long breeding cycles and low predictability associated with these approaches, they no longer meet the demands for high-yield and high-quality varieties in the expansive mushroom market. Modern molecular biology technologies such as RNA interference (RNAi) and gene editing, including via CRISPR-Cas9, can be used to precisely modify target genes, providing a new solution for mushroom breeding. The high-yield genes of mushrooms can be divided into four categories based on existing research results: the genes controlling mycelial growth are very suitable for genetic modification; the genes controlling primordium formation are directly or indirectly regulated by the genes controlling mycelial growth; the genes controlling button germination are more difficult to modify; and the genes controlling fruiting body development can be regulated during the mycelial stage. This article reviews the current research status for the four major categories of high-yield-related genes across the different stages of mushroom growth stages, providing a foundation and scientific basis for using molecular biology to improve mushroom yield and promote the economic development of the global edible-mushroom industry. Full article

Construction of the genome of Hericium coralloides, a species of edible mushroom, and identification of the genes involved in terpenoid biosynthesis can determine the biology and genetics of terpenoids. The present study describes the assembly of a high-quality chromosome-scale genome of H. coralloides using Pacbio HiFi sequencing and Hi-C technology. This genome consisted of 13 chromosomes, a total size of 43.6 Mb, contigs of N50 3.6 Mb, GC content at 54%, and BUSCOs integrity of 96.9%. Genes associated with terpenoid biosynthesis were predicted by KEGG enrichment analysis and homologous alignment. The Her011461 and Her008335 genes, encoding proteins in the terpenoid backbone synthesis pathway, were found to encode geranylgeranyl pyrophosphate and farnesyl diphosphate synthases, key enzymes in the biosynthesis of geranylgeranyl diphosphate, a precursor of several diterpenoids. Her011463 was found to be involved in regulating diterpene cyclase. The Her005433, Her006724, Her010605, and Her010608 genes were found to encode sesquiterpene synthesis. Most of these genes were more highly expressed in dikaryotic mycelia than in the primordium and fruiting bodies, indicating that terpenoids may be more abundant in dikaryotic mycelia. To our knowledge, this study is the first to assemble the H. coralloides genome at the chromosome scale and to identify the genes involved in terpenoid biosynthesis. Full article

Cymbidium ensifolium, a prominent orchid species, is both highly valued for its ornamental qualities and commercially cultivated. However, the species has a considerable challenge in its breeding efforts due to the lengthy period of 7–8 years required for it to transition from seed germination to flowering. BBXs are multifunctional proteins that modulate the actions of critical regulators including HY5 and COP1 in response to blue light, ultimately impacting photomorphogenic processes. In this study, BBX proteins, known for their essential roles in regulating developmental processes under various light conditions, were chosen as the main subject of investigation. The outcome reveals the presence of 19 BBX genes in their genome. The genes are classified into four separate clades and dispersed among 12 out of the 20 chromosomes. Located in the nuclear, physicochemical properties of proteins, analysis of the promoter region reveals the existence of almost 800 cis-acting elements, highlighting the complex regulatory mechanisms that control the expression of the CeBBXs in various organs, as well as their response to light and hormone inputs. Moreover, the examination of differential expression under blue light therapy reveals their involvement in photomorphogenic reactions. The expression of CeBBXs exhibits substantial alterations as the duration of exposure to blue light increases. These findings contribute to a deeper understanding of the roles that BBX genes serve in C. ensifolium, providing a basis for future studies on the functions and regulatory mechanisms of BBX members in the context of floral initiation and development within this species. Full article