Cucumbers (Cucumis sativus L.) are typically monoecious, with both male and female flowers developing on the same plant. Successful fertilization relies on the synchronized release of pollen from the anthers of male flowers and its subsequent germination on the stigma of female flowers. However, the coordinated regulatory mechanisms underlying these processes remain largely unknown. Here, we show that treatment with the JA biosynthesis inhibitor dihydrocoumarin significantly suppresses both anther dehiscence and pollen germination, indicating that JA signaling may regulate male fertility in cucumber. Loss-of-function mutations in the JA receptor COI1 or the JA-signaling transcription factors MYC2a/MYC2b completely abolish anther dehiscence, resulting in complete male sterility. Mechanistic analyses reveal that MYC2a and MYC2b directly bind to the promoters of multiple amylases, including BAM1, BAM5, and AMY3, and activate their transcription. Consistently, loss-of-function alleles of BAM1, BAM5, and AMY3 severely compromise anther dehiscence. Starch degradation in the anther produces substantial quantities of soluble sugars, which are actively transported out from anther; the osmotic potential triggers water outflow from anther, ultimately resulting in anther dehydration and precise dehiscence, as well as pollen release. Collectively, these results demonstrate that JA-mediated starch catabolism serves as a dual-functional regulatory hub: it supplies both the osmotic driving force for anther dehiscence and the metabolic substrates essential for early pollen development. This pathway thus coordinately governs male fertility in cucumber. Our findings identify COI1, MYC2a/MYC2b, and the amylases BAM1, BAM5, and AMY3 as high-priority genetic targets for engineering male sterility and optimizing hybrid seed production in Cucurbitaceae crops.

As a master regulator of seed development, Leafy Cotyledon 1 (LEC1) promotes chlorophyll (Chl) biosynthesis in Arabidopsis , but the mechanism underlying this remains poorly understood. Here, we found that loss of function of OsNF-YB7 , a LEC1 homolog of rice, leads to chlorophyllous embryo, indicating that OsNF-YB7 plays an opposite role in Chl biosynthesis in rice compared with that in Arabidopsis . OsNF-YB7 regulates the expression of a group of genes responsible for Chl biosynthesis and photosynthesis by directly binding to their promoters. In addition, OsNF-YB7 interacts with Golden 2-Like 1 (OsGLK1) to inhibit the transactivation activity of OsGLK1, a key regulator of Chl biosynthesis. Moreover, OsNF-YB7 can directly repress OsGLK1 expression by recognizing its promoter in vivo, indicating the involvement of OsNF-YB7 in multiple regulatory layers of Chl biosynthesis in rice embryo. We propose that OsNF-YB7 functions as a transcriptional repressor to regulate Chl biosynthesis in rice embryo.

Histomonas meleagridis, an anaerobic intercellular parasite, is known to infect gallinaceous birds, particularly turkeys and chickens. The resurgence of histomonosis in recent times has resulted in significant financial setbacks due to the prohibition of drugs used for disease treatment. Currently, research on about H. meleagridis primarily concentrate on the examination of its virulence, gene expression analysis, and the innate immunity response of the host organism. However, there is a lack of research on differentially expressed miRNAs (DEMs) related to liver infection induced by H. meleagridis. In this study, the weight gain and pathological changes at various post-infection time points were evaluated through animal experiments to determine the peak and early stages of infection. Next, High-throughput sequencing was used to examine the expression profile of liver miRNA at 10 and 15 days post-infection (DPI) in chickens infected with the Chinese JSYZ-F strain of H. meleagridis. A comparison with uninfected controls revealed the presence of 120 and 118 DEMs in the liver of infected chickens at 10 DPI and 15 DPI, respectively, with 74 DEMs being shared between the two time points. Differentially expressed microRNAs (DEMs) were categorized into three groups based on the time post-infection. The first group (L1) includes 45 miRNAs that were differentially expressed only at 10 DPI and were predicted to target 1646 genes. The second group (L2) includes 43 miRNAs that were differentially expressed only at 15 DPI and were predicted to target 2257 genes. The third group (L3) includes 75 miRNAs that were differentially expressed at both 10 DPI and 15 DPI and were predicted to target 1623 genes. At L1, L2, and L3, there were 89, 87, and 41 significantly enriched Gene Ontology (GO) terms, respectively (p<0.05). The analysis of differentially expressed miRNA target genes using KEGG pathways revealed significant enrichment at L1, L2, and L3, with 3, 4, and 5 pathways identified, respectively (p<0.05). This article suggests that the expression of liver miRNA undergoes dynamic alterations due to H. meleagridis and the host. It showed that the expression pattern of L1 class DEMs was more conducive to regulating the development of the inflammatory response, while the L2 class DEMs were more conducive to augmenting the inflammatory response. The observed patterns of miRNA expression associated with inflammation were in line with the liver's inflammatory process following infection. The results of this study provide a basis for conducting a comprehensive analysis of the pathogenic mechanism of H. meleagridis from the perspective of host miRNAs.

[目的]探讨影响鸡长链非编码RNA(long chain noncoding RNA,lncRNA)-骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)启动子转录的因素,并对调控lncRNA-BMP4特异表达的分子机制进行研究.[方法]以鸡肌肉基因组为模板,PCR扩增并克隆鸡lncRNA-BMP4的启动子区,构建lncRNA-BMP4-EFGP载体,对lncRNA-BMP4启动活性进行定性分析;通过染色体5'-末端缺失的方法和双荧光素酶系统检测筛选lncRNA-BMP4启动子核心区域.通过在线工具预测分析调控核心区域的潜在转录因子;利用点突变和双荧光素酶系统筛查真正影响lncRNA-BMP4的转录因子;通过表观修饰验证DNA甲基化、组蛋白乙酰化对lncRNA-BMP4的转录调控作用.[结果]试验成功扩增lncRNA-BMP4启动子片段1 288 bp,与pEGFP-N1载体连接后转染鸡成纤维细胞系(DF-1)具有荧光表达,说明lncRNA-BMP4启动子有启动活性.染色体5'-末端缺失和双荧光素酶系统检测发现,核心启动子区域为-832～-651 bp,Jaspar数据库分析筛选到核心区域的转录因子有SOX17、CREB1及STAT1.双荧光素酶系统检测发现,STAT1可促进lncRNA-BMP4核心启动区域的活性;DNA甲基化抑制剂5'-Azacd对lncRNA-BMP4的转录活性未有任何影响,而组蛋白乙酰化抑制剂TSA可极显著提高其转录活性(P＜0.01).[结论]提示lncRNA-BMP4的转录活性受STAT1和组蛋白乙酰化的正调控,而DNA甲基化不影响其转录.研究结果为详细解析lncRNA-BMP4的功能和分子机制提供了理论依据.

Goat (Capra hircus) stearoyl-CoA desaturase 1 (SCD1) plays a crucial role in fatty acid metabolism including milk and muscular fatty acid.This study investigated the expression of SCD1 gene in goat and examined its inheritability and expression in transgenic SCD1 mice and goats.Our results suggested the possibility of generating transgenic goats by sperm-mediated gene transfer (SMGT).The expression of SCD1 gene and fatty acid metabolism genes in goat mammary gland tissues and muscular tissues was aligned with GEO database, and tested by qRT-PCR.F 1 transgenic mice were mated and then the target genes and protein expression level in F 2 transgenic mice, as well as fat content in F 1 and F 2 transgenic mice muscle were examined.Successful transgenic goats generation was identified by testicular injection.The results showed a developmental time specific SCD1 expression in the goat mammary gland tissue and muscular tissue.The rate of positive expression of exogenic gene and exogenic protein in F2 transgenic mice was 30% and 6.67%, respectively, Moreover, muscular fat content in the positive group was significantly higher than the control group both in F1 and F2 (P > 0.05).The rate of positive expression of exogenic gene and exogenic protein was 10.29% and 8.82% in the transgenic goat by testicular injection.Results of the present study showed that SCD1 gene plays a crucial function in goat fatty acid metabolism, and that SCD1 can regulate fat synthesis in SCD1-transferred mice and be inherited stably.Also, SCD1transferred goat could be generated through testicular injection, suggesting a practical approach for transgenic livestock breeding.

Background In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton ( Gossypium hirsutum L.), the relationship between boll setting rate under different planting densities and Bacillus thuringiensis (Bt) insecticidal concentrations in the boll wall were investigated in the present study. Two studies were arranged at Yangzhou, China during the 2017–2018 cotton growth seasons. Five planting densities (15 000, 25 000, 45 000, 60 000 and 75 000 plants per hectare) and the flower-removal treatment were imposed separately on Bt cotton cultivar Sikang3 to arrange different boll setting rates, and the boll setting rates and Bt toxin content were compared. Results Higher boll setting rate together with lower Bt toxin contents in boll wall was observed under low planting density, whereas lower boll setting rate and higher Bt toxin contents were found under high planting density. Also, higher Bt protein concentration was associated with higher soluble protein content, glutamic-pyruvic transaminase (GPT), and glutamic oxaloacetate transaminase (GOT) activities, but lower amino acid content, and protease and peptidase activities. It was further confirmed that a higher boll setting rate with lower Bt protein content under flower-removal. Conclusions This study demonstrated that the insecticidal efficacy of boll walls was significantly impacted by boll formation. Reduced protein synthesis and enhanced protein degradation were related to the reduced Bt toxin concentration.

Gender research shows excellent significance in the breeding and production of poultry, achieving the actual needs of poultry through targeted gender regulation could increase economic benefits. However, the mechanism of sex determination in poultry remains unclear. We respectively constructed HMGCS1 overexpression and interference vectors for lentivirus packaging. Vascular microinjection was performed when fertilized eggs developed to 2.5 days. qRT-PCR and ELISA results indicated that HMGCS1 could promote the expression of male germ-cell development-related genes (SOX9) and inhibit the expression of female germ-cell development-related genes (CYP19A1 and DMRT1). Furthermore, the synthesis of cholesterol and testosterone in the gonads were increased. In addition, the injection of lovastatin into chicken embryos, an inhibitor of cholesterol synthesis, showed a significant decrease in gonadal testosterone. This experiment revealed that HMGCS1 could regulate the synthesis of testosterone by affecting the content of cholesterol in gonads, and promote the differentiation of chicken gonads into males.

植物多聚半乳糖醛酸酶抑制蛋白(polygalacturonase-inhibiting protein,PGIP)可特异性识别病原菌PG(poly-galacturonase),从而提高植物的抗病能力.研究表明水稻中共存在7个OsPGIP基因,为明确OsPGIP家族的蛋白质结构及基因表达特征,从水稻cDNA中扩增各OsPGIP基因序列,经克隆、测序后进行生物信息学分析与蛋白质结构模拟,并测定其在生物逆境与非生物逆境胁迫下的表达量变化.经多序列比较与系统发育进化分析发现,相同或相近物种PGIP往往具有较高的相似性,虽然多数OsPGIP亲缘关系较近,但它们并不能完全聚类在一起.7个OsPGIP蛋白均具有一个信号肽和9～11个LRR片段,各LRR片段中均含有PGIP的特征结构域xxLxLxx.二级结构由 α-螺旋、β-折叠和随机卷曲组成,且多以随机卷曲为主,这些二级结构以重复的随机卷曲—α-螺旋—随机卷曲—β-折叠组成线圈状结构,并按右手螺旋规则形成一个特定的凹面,负责OsPGIP与有害生物PG的互作.7个OsPGIP蛋白多较稳定,且均为疏水蛋白、脂溶性好、具有跨膜结构、定位于细胞外、有1到多个N-糖基化位点、在大肠杆菌中原核表达后基本不溶.经生物和非生物逆境处理后,水稻中不同OsPGIP基因的表达量上下调差异较大,但表达量总和明显上调,说明在逆境条件下水稻可通过调节自身OsPGIP基因的表达量,从而提高其抗逆性.