Sheng wu gong cheng xue bao = Chinese journal of biotechnology最新文献

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and its derivative N-(1,3-dimethylbutyl)-N'-phenyl-p-benzoquinone (6PPD-Q) have been widely detected in the environment and pose potential threats to ecosystems and human health. Given that 6PPD can be equimolarly converted to 6PPD-Q in the environment and organisms, the toxicity differences and molecular mechanisms of action between the two under equimolar exposure remain unclear. This study systematically compared the neurotoxicity and immunotoxicity of the two substances under equimolar conditions. The results from the zebrafish model showed that both 6PPD and 6PPD-Q induced excessive production of reactive oxygen species (ROS) and inhibited the expression of antioxidant enzymes, leading to oxidative damage and immune dyshomeostasis. Meanwhile, they activated the innate immune system and caused an increase in immune cells. In terms of neural development, both disturbed the expression of neurofunctional genes and induced malformations such as pericardial edema, delayed swim bladder closure, and spinal curvature. Notably, at environmentally relevant concentrations, the two showed similar acute toxicity. However, at sublethal levels, 6PPD-Q exhibited stronger toxicity, with oxidative damage, immunotoxicity, teratogenicity, and neurotoxicity being 1-3 times higher than those of 6PPD, and it significantly impaired the sensory and motor abilities of larval fish. The results of real-time quantitative PCR (RT-qPCR) indicated that both substances regulated the expression of neuro- and inflammation-related genes in a dose-dependent pattern. The gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), disease ontology (DO), and hub gene analyses further revealed differences in the molecular-level action focuses between 6PPD and 6PPD-Q. This study provides new evidence for the identification and early warning of the potential risks of 6PPD and 6PPD-Q at environmental and sublethal levels.

Flowering is a critical phase in plant growth and development, regulated by a complex molecular network. The MADS-box transcription factor FRUITFULL (FUL) plays a significant role in controlling flowering time. In order to investigate its function and regulatory mechanism in Rosa chinensis, RcFUL was cloned from the flower buds of R. chinensis 'Old Blush'. Quantitative real-time PCR polymerase results revealed that RcFUL was predominantly expressed in the pistil, and its expression gradually increased during floral development in this variety. Subcellular localization in tobacco showed that RcFUL localized in the nucleus. Silencing RcFULvia virus-induced gene silencing resulted in delayed flowering in TRV-RcFUL plants. Yeast one-hybrid and dual-luciferase reporter assays confirmed that RcSPL1 directly bound to the promoter region of RcFUL. These findings reveal the crucial role of RcFUL in regulation of the flowering time of R. chinensis,expanding the regulatory network underlying the flowering and providing new theoretical insights for the molecular breeding of R. chinensis.

Ethylene, a pivotal gaseous plant hormone regulating plant growth and environmental responses, initiates its signaling through receptor proteins on the membrane. Ethylene response 1 (ETR1) is a key ethylene receptor in plants, and its GAF domain plays a central role in mediating the interaction with the downstream signaling protein ethylene insensitive 2 (EIN2). The research on the interactions between ethylene receptors and downstream components still lacks high-throughput and rapid detection systems, which limits in-depth understanding of the recognition mechanisms. In this study, we utilized the Pichia pastoris expression system to express and purify the transmembrane and GAF domains of ETR1. Membrane proteins were solubilized in the detergent Fos-14 and successfully purified through a two-step strategy involving the Anti-Flag antibody and Ni-NTA affinity chromatography, which yielded high-purity ETR1-GAF protein with structural integrity. Circular dichroism spectroscopy revealed that ETR1-GAF adopted a predominantly α-helical conformation in solution. Using bio-layer interferometry, we conducted kinetic binding assays between ETR1-GAF and the inhibitory peptide NOP-1 at various concentrations. The results revealed a high-affinity, concentration-dependent specific interaction, with a dissociation constant KD=(6.885×10^-5±7.944×10^-6) mol/L, R²=0.991 4. This study establishes a stable and quantifiable in vitro interaction analysis system for ethylene receptors, providing a crucial tool for molecular-level investigation into the dynamic recognition mechanisms between receptors and downstream elements in ethylene signaling. Moreover, it lays a methodological foundation for further exploration of the ethylene signaling network and the development of novel regulatory strategies.

Plant AT-rich protein and zinc-dependent protein (Platz) transcription factors are Zn²⁺-binding and A/T-rich sequence-dependent that primarily function as transcriptional, playing crucial roles in stress responses and the regulation of growth and development. To systematically investigate the biological functions of sorghum Platz transcription factors and their roles in stress responses, we employed bioinformatics and molecular biology techniques to analyze their physicochemical properties, protein secondary structures, subcellular localization, gene structures, phylogenetic relationships, cis-acting elements in the promoter regions, expression patterns, protein-protein interactions, and DNA allelic variations of Platz transcription factors in sorghum. A total of 17 platz genes were identified in sorghum, with uneven distribution across six chromosomes (excluding SBI-02, SBI-03, SBI-05, and SBI-09). These genes encoded unstable hydrophilic proteins with favorable structural fluidity. Significant divergence in gene architecture was observed, and promoter regions were enriched with cis-acting elements linked to abscisic acid (ABA) and methyl jasmonate (MeJA). The phylogenetic analysis divided the platz family in sorghum into five subfamilies. RNA expression patterns of these transcription factors varied across different developmental stages, with platz genes exhibiting the highest expression during the seedling stage. During seed development, SbPlatz7 showed the highest expression, followed by SbPlatz5 and SbPlatz3, while SbFl1a, SbFl1b, SbGl6a, and SbGl6b were also expressed. Notably, drought stress induced upregulated expression of SbRHT25/Platz16 in leaves, whereas low nitrogen conditions and Sporisorium reilianum infection triggered upregulated expression of SbPlatz3 and SbPlatz7. Natural allelic variation analysis revealed frequent frameshift mutations and codon insertions in SbPlatz genes. This study gives novel insights into elucidating the functions of platz in sorghum, offers valuable information for further understanding the evolutionary mechanisms and functional characteristics of the platz gene family in this crop, and provides important references and gene resources for enhancing stress resistance in molecular breeding.

The NHXgenes encode Na⁺/H⁺ transporters, which are cation/proton antiporters and play important roles in plant growth, development, and responses to abiotic stresses. To investigate the NHXgene family members in Brassica juncea and their relationship with salt tolerance, we utilized bioinformatics tools to identify the NHXgene family members in the whole genome of B. juncea and analyzed their gene structures, conserved motifs, evolutionary relationships, promoter cis-acting elements, and gene expression patterns under salt stress. The results showed that a total of 18 BjuNHXs were identified in the genome, encoding hydrophobic proteins with lengths ranging from 451 aa to 1 140 aa, relative molecular weights ranging from 50 308.78 Da to 125 811.24 Da, and theoretical isoelectric points of 5.25-7.71. The secondary structures of the proteins included alpha helices, extended strands, beta turns, and random coils. Among the 18 identified BjuNHXs, their exon number ranged from 13 to 23. All the members harbored motif 4 and motif 5 within the 10 identified conserved motifs. Phylogenetic analysis classified the NHX gene family members into three distinct subfamilies, which exhibited uneven distribution on 11 chromosomes. Promoter cis-acting element analysis showed that the NHX gene family contains different elements that respond to light, plant hormones, and abiotic stresses. The qRT-PCR results showed that both BjuNHX07 and BjuNHX09 exhibited upregulated expression over time of salt treatment. The expression levels of BjuNHX12 and BjuNHX17 in the salt-tolerant variety 'A800' were significantly higher than those in the salt-sensitive variety 'A297'. These results have laid an important foundation for the in-depth study of BjuNHXs and the breeding of salt-tolerant B. juncea varieties.

Sorghum is an important grain and cash crop in China, and the promotion and application of this crop have long been constrained by a shortage of genetic resources. Issues such as narrow genetic background and outdated breeding techniques have severely hindered the development and dissemination of new sorghum varieties. Although gene editing has demonstrated significant potential in the genetic improvement of crops since its inception, the application of this technology in sorghum remains lagging. This paper provides a systematic review of the latest breakthroughs in CRISPR-Cas9 in sorghum. Focusing on abiotic stress, growth and development, and quality, we explore the innovative applications of this technology in expanding genetic diversity, improving stress tolerance, optimizing plant architecture and yield potential, and enhancing quality characteristics. Additionally, we analyze the main technical challenges including low genetic transformation efficiency and insufficient adaptability of editing tools facing the gene editing in sorghum. Finally, we make an outlook on the future prospects of next-generation gene editing technologies in the genetic improvement of sorghum. This paper can provide important theoretical references for sorghum molecular breeding, and hold significant practical significance for safeguarding China's food security and enhancing the competitiveness of the sorghum industry.

Sugarcane smut caused by Sporisorium scitamineum is one of the major diseases of sugarcane. Antimicrobial peptides are eco-friendly agents that can effectively control fungal diseases. The antimicrobial peptide AG-AFP is derived from Aspergillus giganteus and has the advantages of high stability and low biosafety risk. We tested the inhibitory effect of AG-AFP on Sporisorium scitamineum aiming to provide biocontrol resources for diseases in sugarcane. AG-AFP was obtained through prokaryotic expression. We examined the inhibition of AG-AFP on the cell growth of Sporisorium scitamineum and its effects on the integrity and fluidity of the cell membrane to verify the effectiveness of this antimicrobial peptide in the prevention and control of Sporisorium scitamineum. AG-AFP obtained by prokaryotic expression had a good inhibitory effect on Sporisorium scitamineum, with a minimum inhibitory concentration of 23.5 μg/mL. Moreover, it enhanced the cell membrane fluidity, destroyed the cell membrane integrity, and inhibited the dikaryotic hyphae of Sporisorium scitamineum. AG-AFP demonstrates a significant antifungal effect and potential application value for controlling diseases in sugarcane.

Glycerol-3-phosphate acyltransferases (GPATs) are key rate-limiting enzymes that catalyze the biosynthesis of triglycerides (TAG) during the lipid synthesis of oilseed crops. Oat (Avena satiba L.) has the highest fat content among cereal crops, and it is the only gramineous crop that accumulates a large amount of oil in the endosperm. However, the functions of the GPAT genes in oat remain unclear. In this study, 58 genes encoding AsGPATs were identified from the oat genome, and they presented uneven distribution across 20 chromosomes. According to phylogenetic relationships, they were assigned into three different subfamilies. AsGPAT members within the same subfamily exhibited highly conserved gene structures and four conserved acyltransferase domains. The transcriptome sequencing results showed that AsGPAT9-1 had the highest expression level in oat seeds at different developmental stages, and its encoded protein was localized to the endoplasmic reticulum. Functional analysis using a yeast expression system demonstrated that AsGPAT9-1 had strong GPAT activity, which was crucial for TAG assembly. The experiments with exogenous addition of fatty acids (FAs) confirmed that AsGPAT9-1 had a substrate preference for C18:1. Overexpression of AsGPAT9-1 significantly increased the total FA content in the leaves and seeds of transgenic tobacco. Additionally, transgenic tobacco leaves showed reduced starch and soluble sugar content and no significant change in protein level. Moreover, the starch, soluble sugar, and protein content in the seeds of transgenic tobacco all significantly reduced. The results indicated that AsGPAT9-1 served as an ideal target for regulating the FA content of oil crops in genetic metabolic engineering, laying a theoretical foundation for in-depth research on the lipid synthesis and metabolism of oat seeds.

The colors of panicle hull and brown rice are crucial agronomic traits in rice, which are widely used in breeding and genetic research. Here, a rice variety named 'LAL SAR' characterized by golden panicle and brown rice was identified from Nepal. Genetic analysis revealed that these phenotypes were controlled by a single recessive nuclear gene, which was designated as gpr1 (golden panicle and brown rice 1). Using the strategy of map-based cloning, we mapped gpr1 into a 47 kb interval on the rice chromosome 3 and identified its candidate gene as LOC_Os03g60509. This gene encodes a chalcone isomerase, a key enzyme in the flavonoid biosynthetic pathway. Through PCR sequencing and RT-PCR analysis, a long-fragment insertion was found in the promoter of gpr1 in 'LAL SAR', which completely suppressed the expression of this gene. Using CRISPR/Cas9 technology, we successfully knocked out GPR1 (the dominant allele of gpr1) from a Oryza sativa subsp. japonica variety 'Zhonghua 11'. The knockout mutant plants exhibited golden panicles and brown rice, with significantly increased naringenin chalcone content in the hull. Our results indicate that GPR1 participates in the flavonoid biosynthesis, providing a critical theoretical foundation and a gene resource for rice quality improvement and genetic enhancement.

Nanopore sequencing, as an emerging hotspot in sequencing technology, demonstrates tremendous potential in species identification, genome assembly, variant detection, and transcriptome analysis, owing to its distinctive advantages including extended read lengths, rapid detection capabilities, and compact instrumentation. However, nanopore sequencing data are characterized by high error rates and presence of insertions and deletions, which pose novel challenges for the application of conventional sequence alignment tools and the construction of reference databases. Focusing on the characteristics of nanopore data, this paper systematically sorts out sequence alignment tools suitable for nanopore sequencing, and elaborates on their advantages and limitations in processing sequence data for five different application scenarios: long-read sequencing, real-time sequencing, error rate compatibility, metagenomics, and structural variation detection. Meanwhile, from the perspective of data sources, this paper conducts multi-dimensional classification and organization of reference genome databases, and sorts out the key technologies for constructing high-quality nanopore databases. Through the collaborative analysis of alignment tools and databases, this paper provides references for the optimization and innovation of nanopore sequencing data analysis, and promotes the in-depth transformation of metagenomic sequencing from data generation to functional analysis.