This study elucidates endoplasmic reticulum (ER) stress response mechanisms in Brassica campestris at the gene level using high-throughput transcriptome analysis. The productivity of Brassica campestris is severely limited by adverse environmental conditions that trigger ER stress and disrupt cellular homeostasis. However, the molecular mechanisms underlying ER stress responses in B. campestris remain poorly understood. In this study, tunicamycin (TM) and tauroursodeoxycholic acid (TUDCA; TU) were applied to induce and alleviate ER stress, respectively, followed by transcriptome profiling through high-throughput RNA sequencing. A total of 11,728 differentially expressed genes (DEGs) were identified across distinct pairwise comparisons. These DEGs were significantly enriched in GO terms related to oxidative stress response, protein processing in the ER, unfolded protein binding, and protein folding, as well as activated pathways associated with ROS signaling, calcium signaling, and flavonoid biosynthesis. Hierarchical clustering analysis grouped these DEGs into five clusters, of which C1 showed higher expression associated with TM and TU, C2 showed downregulation during ER stress, and C3 showed higher expression in TM treatment. Among DEGs, 351 transcription factors (TFs) were identified under ER stress, with the most abundant families being bZIP (57), NAC (83), MYB (113), HSF (26), and WRKY (72). Weighted gene co-expression network analysis (WGCNA) further identified three co-expression modules (green, brown, and turquoise) comprising 60 key genes, including four unique genes (BraC03g015140, BraC05g046930, BraC08g032210, and BraC09g046280), and 56 hub genes overlapping with DEGs. The identified 60 candidate genes are involved in protein quality control, chaperone activity, ubiquitin-mediated degradation, redox regulation, vesicle trafficking, and metabolic adjustment. Therefore, this study provides a comprehensive transcriptional landscape of ER stress responses in B. campestris, identifies key regulatory genes for functional validation, and offers valuable insights into improving stress resilience in Brassica crops.

Non-heading Chinese cabbage (NHCC), a globally important leafy vegetable, lacks comprehensive nutritional data across its various accessions. This study addressed this gap by quantifying eight essential mineral elements across sixteen NHCC accessions under uniform growing conditions. Results identified potassium (K) and iron (Fe) as the predominant macro- and micro-elements, respectively, with marked physiological partitioning: mobile elements (K, Na) accumulated in the leaf stalk, while others (Ca, Mg, Fe, Zn, Cu, Mn) were concentrated in the leaves. Inter-varietal variation significantly influenced mineral concentrations, evidenced by up to 6.3-fold differences in Cu and 4.2-fold in Fe across accessions. Multivariate analyses identified superior accessions, such as ‘NHCC-084’ and ‘NHCC-070’, characterised by higher mineral content and favourable K/Na ratios. These findings underscore the nutritional potential of specific NHCC varieties for biofortification strategies to address dietary deficiencies and enhance nutritional balance in global diets.

Polyploid plants generally demonstrate enhanced photosynthetic capacity compared to their diploid ancestors; however, the mechanisms underlying this phenomenon remain largely unexplored. This study utilizes pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis] as the material to investigate the molecular mechanisms underlying enhanced photosynthesis in autotetraploid. Our findings indicate that autotetraploid pak choi leaves exhibit increased thickness, enlarged intercellular spaces, and cell dimensions, as well as augmented accumulation of thylakoids and grana. Photosynthesis data indicate that the net photosynthesis (Pn) of autotetraploid plants is significantly greater than that of diploid plants. Transcriptome and miRNA sequencing revealed that the differentially expressed genes were significantly enriched in the photosynthesis thylakoid pathway. Joint analysis revealed that novel-miRNA117 regulates BcLhcb1 and BcLhcb4.2, whereas Bc-miR403-5p regulates BcLhcb4.2. The downregulation of BcLhcb1, BcLhcb2.1, and BcLhcb4.2 resulted in reduced Pn in pak choi, whereas their overexpression increased the growth of Arabidopsis and increased plant weight, which was attributed to the tight stacking of thylakoid granules in the overexpressing plants. Additionally, we observed weakened growth in Arabidopsis overexpressing novel-miRNA117 and Bc-miR403-5p, which was consistent with the phenotype resulting from the silencing of BcLhcbs. These findings further demonstrated that miRNA117 regulates BcLhcb1 and BcLhcb4.2, whereas Bc-miR403-5p regulates BcLhcb2.1. This study enhances our understanding of the molecular mechanisms underlying photosynthesis in homogenous autotetraploid pak choi. Furthermore, it provides novel insights into the regulatory roles of miRNAs in polyploid photosynthesis and contributes to the molecular breeding of pak choi.

JASMONATE ZIM DOMAIN (JAZ) proteins function as negative regulators of the JA signaling pathway and participate in plant development, stress responses, and secondary metabolism. /3-caryophyllene is a volatile sesquiterpene compound that contributes to the formation of plant aromas and possesses antibacterial, anti-inflammatory, and antifungal biological activities. In our previous experiments, we found that the BcJAZ2 was closely related to /3- caryophyllene synthesis under low-temperature treatment in non-heading Chinese cabbage (NHCC). To further explore the function of BcJAZ2, we characterized JAZ gene family in NHCC. In this study, 25 BcJAZ genes were discovered in NHCC, and comprehensively analyzed the evolutionary relationships and structural characterizations of BcJAZs. BcMYC2, a positive regulator of terpenoid synthesis, interacted with BcJAZ2 confirmed by yeast two-hybrid and bimolecular fluorescence complementation assays. Overexpression of BcJAZ2 in Arabidopsis and silencing of BcJAZ2 in NHCC showed that BcJAZ2 acted as a negative regulator of /3-caryophyllene biosynthesis. In addition, three transcription factors BcbHLH137, BcHBI1.1, and BcHBI1.2 were confirmed to be positive regulators of BcJAZ2 by yeast one-hybrid and LUC assays. The above results enrich our understanding of the regulation of /3- caryophyllene synthesis and provide the foundation for in-depth exploration of regulatory mechanisms of BcJAZs.

Flower color is important in determining the ornamental value of Brassica species. However, our knowledge about the regulation of flower color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis] is limited. In this study, we investigated the molecular mechanism underlying white flower traits in pak choi by analyzing a genetic population with white and yellow flowers. Our genetic analysis revealed that the white trait is controlled by a single recessive gene called Bcwf. Through BSA-Seq and fine mapping, we identified a candidate gene, BraC02g039450.1, which is similar to Arabidopsis AtPES2 involved in carotenoid ester synthesis. Sequence analysis showed some mutations in the promoter region of Bcwf in white flowers. Tobacco transient assay confirmed that these mutations reduce the promoter's activity, leading to downregulation of Bcwf expression in white flowers. Furthermore, the silencing of Bcwf in pak choi resulted in lighter petal color and reduced carotenoid content. These findings provide new insights into the molecular regulation of white flower traits in pak choi and highlight the importance of Bcwf in petal coloring and carotenoid accumulation.

In recent years, some components and active ingredients from the herbal formula "eight famous herbals in Zhejiang" (Zhe-Ba-Wei) have been reported to possess antitumor properties. However, there is still no systemic study on the role and mechanism of Zhe-Ba-Wei in cancer. To systematically investigate the anticancer efficacy of Zhe-Ba-Wei, we first identified 17 reported active ingredients with gene targets associated with various types of tumors. Second, we screened these active ingredients and their responding multiple shared targets by analyzing the convergence of diverse and tumor-specific target sites and identified four crucial active ingredients (ferulic acid, quercetin, rutin, luteolin), which were characterized by 27 overlapping gene targets. Third, these 27 gene targets were subsequently mapped onto the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology term, and among the 27 total potential targets, 12 were involved in plasma membrane function. Fourth, we investigated the binding affinities between the four crucial active ingredients and their potential targets such as EGFR and MET, both of which are well-known oncogenes in various cancers. Subsequently, an investigation of the computational ADMET properties showed that most of these four ingredients exhibited good ADMET properties. Finally, we found that three active ingredients (ferulic acid, luteolin, and quercetin) could inhibit the proliferation of non-small cell lung cancer cells and decrease the protein expression of EGFR in a concentration-dependent manner. All these results shed light on the bioactive components, pharmacological effects, and drug development and utilization of Zhe-Ba-Wei, aiming to provide useful support for its further research and clinical application.

APETALA2/ethylene responsive factors respond to ethylene and participate in many biological and physiological processes, such as plant morphogenesis, stress resistance, and hormone signal transduction. Ethylene responsive factor 070 (BcERF070) is important in flowering. However, the underlying molecular mechanisms of BcERF070 in floral transition in response to ethylene signaling have not been fully characterized. Herein, we explored the function of BcERF070 in Pak-choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis]. Ethylene treatment induced BcERF070 expression and delayed flowering in Pak-choi. Silencing of BcERF070 induced flowering in Pak-choi. BcERF070 interacted with major latex protein-like 328 (BcMLP328), which forms a complex with helix-loop-helix protein 30 (BcbHLH30) to enhance the transcriptional activity of BcbHLH30 on LEAFY (BcLFY), ultimately promoting flowering. However, BcERF070 impaired the BcMLP328-BcbHLH30 complex activation of LEAFY (BcLFY), ultimately inhibiting flowering in Pak-choi. BcERF070 directly promoted the expression of the flowering inhibitor gene B-box 29 (BcBBX29) and delayed flowering by reducing FLOWERING LOCUS T (BcFT) expression. These results suggest that BcERF070 mediates ethylene-reduced flowering by impairing the BcMLP328-BcbHLH30 complex activation of BcLFY and by directly promoting the gene expression of the flowering inhibition factor BcBBX29 to repress BcFT expression. The findings contribute to understanding the molecular mechanisms underlying floral transition in response to ethylene in plants. Gene silencing, protein interaction, and transgenesis technology reveal ETHYLENE RESPONSE FACTOR 070 participates in ethylene-mediated inhibition of flowering in Pak-choi.

WRKYs play important roles in plant stress resistance. However, the role of WRKYs in non-heading Chinese cabbage (Brassica campestris ssp. chinensis) against Botrytis cinerea (B. cinerea) remains poorly understood. Herein, the expression of BcWRKY1 was induced by B. cinerea. Further, the role of BcWRKY1 in B. cinerea infection was identified. Silencing of BcWRKY1 in non-heading Chinese cabbage enhanced plant resistance to B. cinerea. After B. cinerea inoculation, BcWRKY1-silencing plants exhibited lower reactive oxygen species (ROS) content, higher jasmonic acid (JA) content, and the expression level of JA biosynthesis genes, BcOPR3, BcLOX3-1 and BcLOX3-2 were upregulated. Overexpression of BcWRKY1 in Arabidopsis exhibited a complementary phenotype. By directly targeting W-boxes in the promoter of BcLOX3-2, BcWRKY1 inhibited the transcription of this gene. In addition, 13 candidate interacting proteins of BcWRKY1 were identified by yeast two-hybrid (Y2H) screening, and the interaction between BcWRKY1 and BcCaM6 weakened the inhibition of BcLOX3-2. In summary, our findings suggest that BcWRKY1 interacts with BcCaM6 to negatively regulate disease resistance.

Pak choi exhibits a diverse color range and serves as a rich source of flavonoids and terpenoids. However, the mechanisms underlying the heterosis and coordinated regulation of these compounds—particularly isorhamnetin—remain unclear. This study involved three hybrid combinations and the detection of 528 metabolites from all combinations, including 26 flavonoids and 88 terpenoids, through untargeted metabolomics. Analysis of differential metabolites indicated that the heterosis for the flavonoid and terpenoid contents was parent-dependent, and positive heterosis was observed for isorhamnetin in the two hybrid combinations (SZQ, 002 and HMG, ZMG). Moreover, there was a high transcription level of flavone 3′-O-methyltransferase, which is involved in isorhamnetin biosynthesis. The third group was considered the ideal hybrid combination for investigating the heterosis of flavonoid and terpenoid contents. Transcriptome analysis identified a total of 12,652 DEGs (TPM > 1) in various groups that were used for comparison, and DEGs encoding enzymes involved in various categories, including “carotenoid bio-synthesis” and “anthocyanin biosynthesis”, were enriched in the hybrid combination (SZQ, 002). Moreover, the category of anthocyanin biosynthesis also was enriched in the hybrid combination (HMG, ZMG). The flavonoid pathway demonstrated more differential metabolites than the terpenoid pathway did. The WGCNA demonstrated notable positive correlations between the dark-green modules and many flavonoids and terpenoids. Moreover, there were 23 ERF genes in the co-expression network (r ≥ 0.90 and p < 0.05). Thus, ERF genes may play a significant role in regulating flavonoid and terpenoid biosynthesis. These findings enhance our understanding of the heterosis and coordinated regulation of flavonoid and terpenoid biosynthesis in pak choi, offering insights for genomics-based breeding improvements.

MAX2（MORE AXILLARY GROWTH 2）is a gene associated with strigolactone signal transduction. Its function is related to the growth of axillary buds. The effects of MAX2 on the growth of axillary buds were investigated by using the multiple shoot branching cultivar‘Maertou’and common cultivar‘Suzhouqing’. The results showed that there were no differences in the ORF（Open Reading Frame）sequence of BcMAX2 gene obtained from the two materials， but the BcMAX2 promoter sequence of ‘Maertou’has a two-base deletion. Subcellular localization analysis indicated BcMAX2 localization in the nucleus. Overexpression of BcMAX2 in Arabidopsis increased BRC1 expression and inhibited axillary bud growth. Silencing of BcMAX2 in‘Maertou’caused the decrease of BcBRC1 expression and promoted the growth of axillary buds. Total of 197 candidate proteins interacting with BcMAX2 were obtained from the cDNA library of Brassica campestris ssp. chinensis. Most of the candidate proteins had binding and catalytic activities，and some of them were involved in signal transduction and stress response of plants. Two interacting proteins were verified by yeast two-hybrid system and bimolecular fluorescence complementation technique. The study showed that BcMAX2 may negatively regulate axillary bud growth by promoting BcBRC1 expression.

FLOWERING LOCUS T（FT） is a key gene in the regulation of plant flowering pathways. When comparing the promoters of BcFT in late-flowering wym-97 and early-flowering cx-49 cultivars, it was found that there was a 1 577 bp insertion in the BcFT promoter of cx-49. In order to explore the effect of the inserted fragment on the flowering of non-heading Chinese cabbage, a yeast hybrid cDNA library of non-heading Chinese cabbage was constructed, and the interacting protein with the BcFT promoter was screened by yeast one-hybrid technology. The results showed that the library capacity of the cDNA library obtained in this study was 1. 8×10~6 CFU, and the recombination rate was 100%. The length distribution of the inserts ranged from about 400 to 2 000 bp, and the average length was greater than 1 000 bp, indicating that the non-heading cabbage yeast hybrid cDNA library was successfully constructed. In addition, the self-activation assay showed that 800 ng·mL -1 of AbA could inhibit the self-activation of the bait vector. The upstream proteins BcSAP18and BcDEAR2 that bind the BcFT promoter insert were screened by yeast one-hybrid assay. Therefore, this study successfully constructed a non-heading cabbage yeast hybrid cDNA library and obtained the interaction protein of the BcFT promoter insert, which laid the foundation for further research on the regulatory mechanism of the BcFT in the flowering of non-heading cabbage.

In order to obtain new materials of homologous tetraploid nonbearing Chinese cabbage Lcx025b with high quality anthocyanin, the cotyledon growth point of diploid Lcx025b seedlings was treated with colchicine solution of 0. 2%（w/v） concentration. The homologous tetraploid plants were screened and identified by morphological, cytological and flow cytometry methods. The diploid and tetraploid plants were compared and analyzed by agronomic traits, nutritional quality, photosynthetic characteristics and disease resistance. The results showed that compared with diploid plants, tetraploid plants showed giant morphology, the ratio of length to width of leaves decreased significantly, the leaves tended to be oblate, the flower organs, seed pods and seeds increased significantly, and the color of cabbage moss deepened. Stomatal density decreased and stomatal density increased significantly. The pollen grains showed obvious irregularity. The number of chromosomes in root tip cells of tetraploid plants and the fluorescence intensity of DNA of tetraploid plants analyzed by flow cytometry were twice that of diploid plants. In terms of nutritional quality, the contents of soluble sugar and chlorophyllin increased significantly, the contents of cellulose and nitrate nitrogen decreased significantly, and the contents of soluble protein and chlorophyll had no significant difference. Combined with the light response curve analysis, the tetraploid has stronger photosynthetic capacity and higher adaptability.In addition, the resistance of tetraploid plants to P. cinerea was obviously better than that of diploid plants. In conclusion, through this study, a new material of homologous tetraploid Lcx025b with high anthocyanin, purple cai-tai, was obtained, which provided important material support for the innovation of germplasm resources of non-knoting Chinese cabbage.

[Objectives]The purpose of this study was to investigate the effects of different ages on the slaughter performance, muscle quality and nutritional characteristics of 817 broilers. [Methods]Using 35,42 and 49 day-old 817 broilers as experimental materials, the slaughter performance at different ages, the muscle quality of chicken breasts（pH value, water retention, color, and shear force, moisture distribution, texture, muscle fiber diameter）,and nutritional indicators（basic chemical composition, the composition of amino acid and fatty acid）were measured. [Results]With the increase of age, the half-eviscerated yield percentage, eviscerated yield percentage, breast muscle percentage, leg muscle percentage and abdominal fat percentage of 817 broilers significantly increased（P＜0.05）. The pH 24 h value, L * value, a * value, shear force value, bound water content, muscle fiber diameter, hardness, adhesiveness, crude protein, crude fat, ash, essential amino acids and saturated fatty acids content of breast meat significantly increased. However, cooking loss rate, drip loss rate, the relaxation time(T 2b ),and the content of moisture and monounsaturated fatty acid significantly reduced. Pearson correlation analysis results showed that pH 24 h value was negatively correlated with cooking loss rate, drip loss rate, T 2b ,but positively correlated with bound water content; shear force value was positively correlated with hardness, muscle fiber diameter and crude protein, but negatively correlated with the cooking and drip loss rate. [Conclusions]With the increase of age, the meat production performance of 817 broilers improved, the water retention and color became better, and the nutritional value increased, but the hardness increased and the tenderness decreased.

Non-heading Chinese cabbage (Brassica campestris ssp. chinensis) is an important vegetative crop in the south of China. As an antioxidant, anthocyanin is the major quality trait for vegetables with purple leaves or petioles. However, the molecular biosynthetic mechanism of anthocyanin in non-heading Chinese cabbage has not been explained exclusively. In this study, two non-heading Chinese cabbage with contrasting colors in the leaves were used as the materials for RNA-seq. A total of 906 DEGs were detected, and we found that the anthocyanin and flavonoid biosynthetic pathways are significantly enriched in the purple NHCC. The transcriptome result was verified by RT-qPCR. Though bioinformatics analysis, BcTT8 was selected as the candidate gene for the regulation of anthocyanin synthesis, and the characterization of BcTT8 was elucidated by the functional analyses. The results proved that BcTT8 is a nucleus protein and phylogenetically close to the TT8 protein from Brassica. After silencing BcTT8, the total anthocyanin content of pTY-BcTT8 plants decreased by 42.5%, and the relative expression levels of anthocyanin pathway genes BcDFR, BcLODX and BcUF3GT-1 were significantly downregulated, while the transcription level of BcFLS was significantly upregulated. Compared with the wild type, the transgenic Arabidopsis showed obvious violet in the cotyledons part, and the anthocyanin biosynthetic genes such as AtDFR and AtLODX were significantly upregulated. In conclusion, BcTT8 is critical in the anthocyanin synthesis process of non-heading Chinese cabbage. Our findings illustrated the molecular mechanism of anthocyanin biosynthesis in non-heading Chinese cabbage.

为深入了解洋葱研究的发展现状、研究热点和前沿趋势,以2000-2020年Web of Science(WoS)数据库和中国知网(CNKI)数据库收录的洋葱研究论文为数据来源,利用文献计量学方法,运用Citespace和Excel等软件对发文量、主要发文国家和机构、研究主题、研究前沿等进行统计分析.结果显示:1)WoS关于洋葱研究的发文量呈现逐年上升的趋势,主要出自美国、印度和日本等国家,总占比超过38％;以印度农业研究委员会、美国农业部和美国乔治亚大学等研究机构发文量最高;高水平的文献主要出 自美国、日本和韩国等国家的研究机构、学者和期刊.2)CNKI关于洋葱研究的发文量呈现先上升后逐步回落的趋势,发文机构主要包括连云港市农业科学院、东北农业大学和山东农业大学等,总占比超过10％;高水平的文献主要出 自北京理工大学、浙江大学和南京农业大学等院校;具有较高影响因子的期刊数量较少.3)国内外研究热点表现出趋同的发展趋势,专注于洋葱营养品质、抗氧化活性、栽培技术、品种选育和病虫害防治等方面;关键词突发性检测表明针对洋葱的酚类化合物、植物促根际细菌、间套作及综合利用等领域可能为研究前沿.以上计量分析结果可为洋葱的深入研究及促进其产业发展提供参考与借鉴.

The purpose of this study was to explore the regulation of BcMYB44 on anthocyanin synthesis and drought tolerance of non-heading Chinese cabbage. The BcMYB44 gene was cloned from the purple inbred line 'NJZX1-3' and its green mutant 'NJZX1-0'. Sequence analysis confirmed that BcMYB44 belongs to the R2R3-MYB family and has the highest homology with BnMYB44. Subcellular localization revealed that BcMYB44 is a nuclear protein. Yeast two-hybrid (Y2H) and Bimolecular Fluorescent Complimentary (BiFC) experiments showed that BcMYB44 interacts with BcPAP1 and BcEGL3. Pigment detection of BcPAP1 and BcMYB44 protein activity in N. benthamiana indicates that BcMYB44 plays a negative regulatory role by inhibiting the expression of key structural genes (F3H, DFR, etc.) in anthocyanin synthesis. Virus-induced gene silencing (VIGS) further confirmed this inhibition. Analysis of drought tolerance of non-heading Chinese cabbage based on VIGS showed that pTY-S plants are more resistant to drought than pTY-BcMYB44 plants. The results indicate that BcMYB44 has a positive regulatory role in drought stress, which most likely is achieved by inhibiting anthocyanin accumulation, regulating stomatal movement, and improving osmotic regulation and homeostasis of reactive oxygen species (ROS).

不结球白菜黄心乌是长江中下游流域特别是安徽地区的主栽品种之一.为获得品质优良的黄心乌新材料,本研究使用0.2％(w/v)的秋水仙素溶液点滴处理二倍体黄心乌幼苗的子叶生长点,通过形态学和细胞学的方法筛选到同源四倍体黄心乌植株,并对二、四倍体黄心乌的农艺性状以及品质进行分析.形态学研究结果表明,四倍体植株的株型、叶片、花、种荚表现出巨大型;四倍体叶片的气孔变大,气孔密度变小;花粉粒体积比二倍体变大且呈现出棒状.细胞学分析结果发现,四倍体植株的根尖染色体数目是二倍体的2倍.流式细胞仪分析结果表明,四倍体植株的荧光强度为二倍体的2倍.营养品质方面,与二倍体相比,四倍体纤维素、有机酸含量显著上升,叶绿素、硝态氮含量显著下降,可溶性糖及可溶性蛋白含量无显著变化.此外,结合光响应曲线分析结果发现,强光条件下,四倍体对光强的适应能力更强.在抗病性检测中发现,四倍体的灰霉菌抗性明显优于二倍体.本研究获得了高产、抗病的同源四倍体不结球白菜黄心乌新材料,为不结球白菜育种工作提供了新的种质资源.

[目的]本文旨在研究不同解冻方式对817肉鸡食用品质和肌原纤维蛋白特性的影响.[方法]以鸡胸肉为试验材料,将其置于-20℃冷冻24 h,分别用空气[KQ,(25±1)℃]、流水[LS,(25±1)℃]、超声波[CS,200 W,(25±1)℃]和低温[DW,(4±1)℃]4种方式进行解冻,测定解冻时间、pH值、保水性、色泽、剪切力、水分分布以及肌原纤维蛋白(MP)溶解度、粒径、总巯基含量、二级和三级结构等指标.[结果]与其他处理组相比,LS组解冻时间最短(24.2 min),L?值最高(53.11),剪切力值最低(17.85 N);LS组解冻、蒸煮和滴水损失率显著低于KQ和DW组,MP溶解度和总巯基含量显著高于KQ和DW组;LS组T2弛豫时间最短,结合水和不易流动水含量最多,α-螺旋含量和内源性荧光光谱强度最高.[结论]流水解冻的鸡胸肉色泽、嫩度和保水性最佳,肌原纤维蛋白的聚集和氧化程度小,二级和三级结构稳定.

[目的]本文旨在研究紫菜薹BrbHLH49基因在花青素合成中的功能.[方法]以紫菜薹为材料,通过同源克隆获得BrbHLH49基因全长序列,并与其他物种中的同源序列进行进化树分析;构建pEarlyGate101-BrbHLH49-YFP载体并转化导入烟草叶片中,研究BrbHLH49蛋白的亚细胞定位;采用荧光定量PCR(RT-qPCR)技术分析BrbHLH49基因在紫菜薹和'四九菜心'('CX-49')不同组织中的表达情况,同时分析野生型和35S:BrbHLH49-YFP转基因拟南芥中花青素合成相关基因的表达.[结果]BrbHLH49基因含有1431 bp开放阅读框,编码476个氨基酸,其编码的蛋白定位于细胞核中.在进化过程中BrbHLH49编码的氨基酸序列与甘蓝型油菜和野甘蓝(原变种)同源性最高,亲缘关系最近.RT-qPCR结果表明,紫菜薹的薹和叶中BrbHLH49相对表达量均显著高于'CX-49',且BrbHLH49转基因拟南芥植株中花青素合成相关基因的表达量显著高于野生型.[结论]BrbHLH49蛋白定位于细胞核中.BrbHLH49基因在紫菜薹的薹和叶中高表达,且拟南芥中过表达该基因能显著提高花青素的合成.

[目的]本文旨在探究BcEGL3基因在不结球白菜紫色材料和其绿色突变体中的特性及其调控功能.[方法]以不结球白菜紫色自交系NJZX1-3和其绿色突变体NJZX1-0为材料,克隆BcEGL3基因;构建表达载体pRI101-BcEGL3,进行亚细胞定位;构建沉默载体pTY-BcEGL3,分析材料中花青苷含量变化,以及BcEGL3、BcDFR基因在NJZX1-3、NJZX1-0、pTY-S和pTY-BcEGL3植株的基因表达量;对NJZX1-3进行遮光处理,分析遮光后花青苷的积累以及BcEGL3基因的转录水平变化.[结果]从NJZX1-3和NJZX1-0中克隆所得EGL3基因序列完全相同,序列长1821 bp,含1个1818 bp的开放阅读框(ORF),编码606个氨基酸,将其命名为BcEGL3.蛋白结构分析表明,EGL3蛋白属于bHLH-MYC-N超家族,其蛋白结构较为简单.进化树结果表明,BcEGL3蛋白与大白菜BraEGL3关系最近,同源性高达99.9％.亚细胞定位结果显示,BcEGL3蛋白定位于细胞核中.基因沉默结果表明,与NJZX1-3相比,转pTY-BcEGL3或pTY-S植株叶片紫色变浅,且对应花青苷含量降低.RT-qPCR结果表明,BcEGL3和BcDFR基因在转pTY-BcEGL3植株中的相对表达量低于转pTY-S植株和NJZX1-3植株,同时植株叶片颜色由紫色转为绿色,花青苷含量明显降低,但总叶绿素含量及类胡萝卜素含量无明显变化.遮光处理5 d后不结球白菜叶片中花青苷的含量比对照下降68％,且11 d时叶片中花青苷含量降幅最大.另外,遮光后BcEGL3基因相对表达量呈下降趋势,与对照相比14 d时下降幅度最大.[结论]BcEGL3蛋白定位于细胞核,BcEGL3基因沉默可以抑制叶片中花青苷的合成,且与BcDFR基因的表达密切相关,因此在不结球白菜花青苷的合成过程中BcEGL3基因起重要作用.