MicroRNA-370-5p inhibits pigmentation and cell proliferation by downregulating mitogen-activated protein kinase kinase kinase 8 expression in sheep melanocytes

In mammals, microRNAs (miRNAs) play key roles in multiple biological processes by regulating the expression of target genes.  Studies have found that the levels of miR-370-5p expression differ significantly in the skins of sheep with different hair colors; however, its function remains unclear.  In this study, we investigated the roles of miR-370-5p in sheep melanocytes and found that the overexpression of miR-370-5p significantly inhibited cell proliferation (P<0.01), tyrosinase activity (P=0.001) and significantly reduced (P<0.001) melanin production.  Functional prediction revealed that the 3´-untranslated region (UTR) of MAP3K8 has a putative miR-370-5p binding site, and the interaction between these two molecules was confirmed using luciferase reporter assays.  In situ hybridization assays revealed that MAP3K8 is expressed in the cytoplasm of melanocytes.  The results of quantitative RT-PCR and Western blotting analyses revealed that overexpression of miR-370-5p in melanocytes significantly inhibits (P<0.01) MAP3K8 expression via direct targeting of its 3´ UTR.  Inhibition of MAP3K8 expression by siRNA-MAP3K8 transfection induced a significant inhibition (P<0.01) of melanocyte proliferation and significant reduction (P<0.001) in melanin production, which is consistent with our observations for miR-370-5p.  Target gene rescue experiments indicated that the expression of MAP3K8 in melanocytes co-transfected with miR-370-5p and MAP3K8-cDNA (containing sites for the targeted binding to miR-370-5p) was significantly rescued (P≤0.001), which subsequently promoted significant increases in cell proliferation (P<0.001) and melanin production (P<0.01).  Collectively, these findings indicate that miR-370-5p plays a functional role in inhibiting sheep melanocyte proliferation and melanogenesis by downregulating the expression of MAP3K8.       

Diamide derivatives containing a trifluoromethylpyridine skeleton: Design,synthesis, and insecticidal activity

Diamide derivatives are biologically active molecules that have been widely applied in recent years in research on pesticides, especially insecticides.  Using a simple and environmentally friendly scheme, a series of new diamide derivatives containing a trifluoromethylpyridine skeleton was designed, synthesized, and confirmed by ¹H, ¹⁹F and ¹³C NMR, and HR-MS.  Their insecticidal activities against Plutella xylostella and Helicoverpa armigera were measured and the relationship between structure and activity was investigated.  Eight of the title compounds (D2, D5, D10, D21, D28, D29, D30 and D33) showed 100% activity against P. xylostella at 500 mg L^–1.  One compound, D33, still showed 100% activity against P. xylostella at 100 mg L^–1 and had the lowest LC₅₀ (lethal concentration 50%, 3.7 mg L^–1) among the synthesized compounds.  Molecular docking analysis revealed that D33 could be thoroughly embedded in the active pocket of the ryanodine receptor via hydrogen bonding in a manner similar to the commercial insecticide chlorantraniliprole.     

Dietary copper supplementation modulates performance and lipid metabolism in meat goat kids

Forty-eight male Lezhi black goat kids with similar body weight ((12.09±1.70) kg) and age ((60±5) d) were used to determine the effect of dietary copper (Cu), in the form of reagent grade Cu sulfate (CuSO₄∙5H₂O), on performance, serum lipid profile, and the relative mRNA abundance of genes involved in lipid metabolism.  Goat kids were stratified by body weight and randomly assigned to one of 4 treatment groups.  Each treatment consisted of 12 replicate pens with each pen containing one goat kid.  Treatment groups received the basal diet with no supplemental Cu (control), basal diet plus 10 mg of Cu kg^–1 of dry matter (DM), basal diet plus 20 mg of Cu kg^–1 of DM, or basal diet plus 30 mg of Cu kg^–1 of DM.  Goats were housed individually in pens and fed a high-concentrate pelleted diet for 60 d.  Average daily gain, average daily feed intake and feed:gain of goats were not affected by dietary Cu supplementation (P>0.10).  No differences were detected in serum total cholesterol, triglyceride, and high density lipoprotein cholesterol concentrations of goat kids fed with different Cu concentrations (P>0.05).  However, serum low density lipoprotein cholesterol concentrations decreased linearly (P=0.01) as the concentration of dietary Cu increased.  Intramuscular fat content of longissimus muscle increased (P=0.002) quadratically and liver Cu concentrations increased (P<0.001) linearly as dietary Cu concentration increased.  Compared with the control, dietary supplementation of 20 mg Cu kg^–1 DM decreased the relative mRNA abundance of fatty acid-binding protein 4 (P=0.01) and lipoprotein lipase (P=0.05), and tended to decrease the relative mRNA abundance of carnitine palmitoyltransferase I (P=0.06) in longissimus muscle of goats.  The relative mRNA abundance of peroxisome proliferator-activated receptor alpha (P<0.001), carnitine acetyltransferase (P=0.001), and carnitine palmitoyltransferase I (P=0.001) were also decreased in liver by Cu supplementation.  These results indicate that dietary supplementation of Cu modified lipid metabolism by increasing muscular fat and decreasing serum low density lipoprotein cholesterol, and the modification might be associated with the reduction of relative mRNA abundance of genes for oxidation of long-chain fatty acid in muscle and liver of Lezhi black goat kids.     

Biosynthesis of artemisinic acid in engineered Saccharomyces cerevisiae and its attractiveness to the mirid bug Apolygus lucorum

Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in autumn.  Volatiles emitted from A. annua attract A. lucorum.  Volatile artemisinic acid of A. annua is a precursor of artemisinin that has been widely investigated in the Chinese herbal medicine field.  However, little is known at this point about the biological roles of artemisinic acid in regulating the behavioral trends of A. lucorum.  In this study, we collected volatiles from A. annua at the seedling stage by using headspace solid phase microextraction (HS-SPME).  Gas chromatography-mass spectrometry (GC-MS) analysis showed that approximately 11.03±6.00 and 238.25±121.67 ng h^–1 artemisinic acid were detected in volatile samples and milled samples, respectively.  Subsequently, a key gene for artemisinic acid synthesis, the cytochrome P450 gene cyp71av1, was expressed in engineered Saccharomyces cerevisiae to catalyze the production of artemisinic acid.  After the addition of exogenous artemisinic alcohol or artemisinic aldehyde, artemisinic acid was identified as the product of the expressed gene.  In electroantennogram (EAG) recordings, 3-day-old adult A. lucorum showed significant electrophysiological responses to artemisinic alcohol, artemisinic aldehyde and artemisinic acid.  Furthermore, 3-day-old female bugs were significantly attracted by artemisinic acid and artemisinic alcohol at a concentration of 10 mmol L^–1, whereas 3-day-old male bugs were attracted significantly by 10 mmol L^–1 artemisinic acid and artemisinic aldehyde.  We propose that artemisinic acid and its precursors could be used as potential attractant components for the design of novel integrated pest management strategies to control A. lucorum.     

Use of transcriptome sequencing to explore the effect of CSRP3 on chicken myoblasts

The mechanisms that regulate the specificity and maintenance of chicken muscle fiber types remain largely unknown. In mammals, CSRP3 has been shown to play a vital role in the maintenance of typical muscle structure and function. This study investigated the role that CSRP3 plays in chicken skeletal muscle. First, the antibody against chicken CSRP3 protein was prepared, and the expression levels of the mRNA and protein of the CSRP3 gene in four chicken skeletal muscles with different myofiber com...     

Establishment of an efficient regeneration and genetic transformation system for Malus prunifolia Borkh. ‘Fupingqiuzi’

Malus prunifolia Borkh. ‘Fupingqiuzi’ has significant ecological and economic value and plays a key role in germplasm development and resistance research.  However, its long juvenile phase and high heterozygosity are barriers to the identification of ‘Fupingqiuzi’ progeny with excellent traits.  In-vitro regeneration techniques and Agrobacterium-mediated genetic transformation systems can efficiently produce complete plants and thus enable studies of gene function.  However, optimal regeneration and genetic transformation systems for ‘Fupingqiuzi’ have not yet been developed.  Here, we evaluated the factors that affect the in-vitro regeneration and transformation of ‘Fupingqiuzi’.  The best results were obtained when transverse leaf sections were used as explants, and they were grown in dark culture for three weeks with their adaxial sides contacting the culture medium (MS basal salts, 30 g L⁻¹ sucrose, 8 g L⁻¹ agar, 5 mg L⁻¹  6-benzylaminopurine (6-BA), 2 mg L⁻¹ thidiazuron (TDZ), and 1 mg L⁻¹ 1-naphthlcetic acid (NAA), pH 5.8).  A genetic transformation system based on this regeneration system was optimized: after inoculation with A. tumefaciens solution for 8 min, 4 days of co-culture, and 3 days of delayed culture, the cultures were screened with cefotaxime (150 mg L⁻¹) and kanamycin (15 mg L⁻¹).  We thus established an efficient regeneration and genetic transformation system for ‘Fupingqiuzi’, enabling the rapid production of transgenic material.  These findings make a significant contribution to apple biology research     

Quantifying in situ N2 fluxes from an intensively managed calcareous soil using the 15N gas-flux method

Denitrification-induced nitrogen (N) losses from croplands may be greatly increased by intensive fertilization.  However, the accurate quantification of these losses is still challenging due to insufficient available in situ measurements of soil dinitrogen (N₂) emissions.  We carried out two one-week experiments in a maize–wheat cropping system with calcareous soil using the ¹⁵N gas-flux (¹⁵NGF) method to measure in situ N₂ fluxes following urea application.  Applications of ¹⁵N-labeled urea (99 atom%, 130–150 kg N ha⁻¹) were followed by irrigation on the 1st, 3rd, and 5th days after fertilization (DAF 1, 3, and 5, respectively).  The detection limits of the soil N₂ fluxes were 163–1 565, 81–485, and 54–281 μg N m⁻² h⁻¹ for the two-, four-, and six-hour static chamber enclosures, respectively.  The N₂ fluxes measured in 120 cases varied between 159 and 2 943 (811 on average) μg N m⁻² h⁻¹, which were higher than the detection limits, with the exception of only two cases.  The N₂ fluxes at DAF 3 were significantly higher (by nearly 80% (P<0.01)) than those at DAF 1 and 5 in the maize experiment, while there were no significant differences among the irrigation times in the wheat experiment.  The N₂ fluxes and the ratios of nitrous oxide (N₂O) to the N₂O plus N₂ fluxes following urea application to maize were approximately 65% and 11 times larger, respectively (P<0.01), than those following urea application to wheat.  Such differences could be mainly attributed to the higher soil water contents, temperatures, and availability of soil N substrates in the maize experiment than in the wheat experiment.  This study suggests that the ¹⁵NGF method is sensitive enough to measure in situ N₂ fluxes from intensively fertilized croplands with calcareous soils.     

Effects of grape seed extract on meat color and premature browning of meat patties in high-oxygen packaging

This study investigated the effects of grape seed extract (GSE) on fresh and cooked meat color and premature browning (PMB) in ground meat patties (85% beef and 15% pork back fat) packaged under high-oxygen modified atmospheres (HiOx-MAP).  The GSE was added to patties at concentrations of 0, 0.10, 0.25, 0.50 and 0.75 g kg^–1.  This study evaluated the surface color, pH, lipid oxidation, and total viable counts (TVC) of raw patties, and the internal color and pH of patties cooked to a temperature of 66 or 71°C over 10-day storage at 4°C.  Compared with the control (0 g kg^–1 GSE), GSE improved the color stability (P<0.05) and significantly inhibited the lipid and myoglobin oxidation of raw patties from day 5 to 10, but GSE had no effect (P>0.05) on TVC.  Patties containing 0.50 and 0.75 g kg^–1 GSE cooked to 66°C exhibited greater (P<0.05) interior redness than the control and reduced the PMB of cooked patties in the late storage stage.  These results suggested that 0.50 and 0.75 g kg^–1 GSE can improve fresh meat color and minimize PMB of HiOx-MAP patties.     

Nonphytotoxic copper oxide nanoparticles are powerful “nanoweapons” that trigger resistance in tobacco against the soil-borne fungal pathogen Phytophthora nicotianae

Investigations into the potential application of nanoparticles acting as nanofungicides in sustainable agriculture are rapidly expanding due to the high antimicrobial properties of these compounds, which do not risk inducing pathogen resistance to fungicides.  A detailed understanding of the impact of copper oxide nanoparticles (CuO NPs) on soil-borne phytopathogenic fungi is yet to be obtained.  This study aimed to explore the in vitro antifungal activity and control efficacy of CuO NPs applied via irrigation with respect to tobacco black shank (TBS) disease caused by Phytophthora nicotianae.  The results revealed that CuO NPs greatly interfered with the reproductive growth process of this fungus, repressing hyphal growth, spore germination and sporangium production.  Additionally, morphological damage, intracellular ROS accumulation and increased SOD enzyme activity in hyphae were the antifungicidal mechanisms of these NPs.  In pot experiments, treatment with CuO NPs at 100 mg L^–1 significantly suppressed TBS development, compared with the effect on control plants, and the control efficacy reached 33.69% without inducing phytotoxicity.  Exposure to CuO NPs significantly activated a series of defense enzymes, and resistance genes in tobacco can further explain the mechanisms by which CuO NPs suppressed fungal infection.  The Cu content in both the leaves and roots of P. nicotianae-infested plants increased by 50.03 and 27.25%, respectively, after treatment with 100 mg L^–1 CuO NPs, compared with that of healthy plants.  In particular, a higher Cu content was observed in infected roots than in leaves.  Therefore, this study showed the potential of CuO NPs applied as nanofungicides and as nanoinducers of fungus resistance genes for the management of TBS through inhibition of pathogen infection and stimulation of plant defenses.     

In vitro and in silico studies of salicylic acid on systemic induced resistance against bacterial leaf blight disease and enhancement of crop yield

Salicylic acid (SA) is an effective elicitor to promote plant defenses and growth.This study aimed to investigate rice(Oryza sativa L.) cv.Khao Dawk Mali 105 treated with salicylic acid (SA)-Ricemate as an enhanced plant protection mechanism against bacterial leaf blight (BLB) disease caused by Xanthomonas oryzae pv.oryzae (Xoo).Results indicated that the use of SA-Ricemate as a foliar spray at concentrations of more than 100 mg L^–1 can reduce the severity of BLB disease by 71%.SA-Ric...     

甘加型藏羊发情周期下丘脑-垂体-卵巢轴中ERβ mRNA及其蛋白的表达

为阐明甘加型藏羊(Ovis arise)发情周期下丘脑-垂体-卵巢(hypothalamic-pituitary-ovarian axis, HPO)轴中雌激素受体β(estrogen receptor β,ERβ)mRNA和蛋白的表达及分布,本试验选取健康且在发情周期内的甘加型藏羊32只,运用qRT-PCR、Western blot 技术和免疫组织化学染色法检测甘加型藏羊发情周期ERβ mRNA及蛋白在HPO轴中的表达和分布差异。结果显示,甘加型藏羊整个发情周期(发情前期、发情期、发情后期及间情期)ERβ mRNA及其蛋白在HPO轴中均有表达和分布。下丘脑中ERβ mRNA及其蛋白在下丘脑中发情前期表达最多,显著高于其他3个时期(P<0.05);垂体中ERβ mRNA及蛋白均在发情前期表达最高,与其他3个时期差异显著(P<0.05);在卵巢中间情期表达最高,显著高于其他3个时期(P<0.05)。免疫组织化学染色结果显示,ERβ阳性表达主要分布在下丘脑大神经元胞体和轴突中;在垂体中多分布在远侧部及中间部嗜酸性细胞胞浆中,胞核中分布较少;在卵巢中,生长卵泡颗粒细胞胞浆和胞核、卵泡内膜细胞及黄体细胞胞浆中均有分布。ERβ mRNA及其蛋白在甘加型藏羊发情周期HPO轴的差异性表达表明雌激素受体β参与调节甘加型藏羊的生殖生理活动。     

Investigation of Aegilopsumbellulatafor stripe rust resistance,heading date,and the contents of iron,zinc, and gluten protein

Aegilops umbellulata (UU) is a wheat wild relative that has potential use in the genetic improvement of wheat.  In this study, 46 Ae. umbellulata accessions were investigated for stripe rust resistance, heading date (HD), and the contents of iron (Fe), zinc (Zn), and seed gluten proteins.  Forty-two of the accessions were classified as resistant to stripe rust, while the other four accessions were classified as susceptible to stripe rust in four environments.  The average HD of Ae. umbellulata was significantly longer than that of three common wheat cultivars (180.9 d vs. 137.0 d), with the exception of PI226500 (138.9 d).  The Ae. umbellulata accessions also showed high variability in Fe (69.74–348.09 mg kg^–1) and Zn (49.83–101.65 mg kg^–1) contents. Three accessions (viz., PI542362, PI542363, and PI554399) showed relatively higher Fe (230.96–348.09 mg kg^–1) and Zn (92.46–101.65 mg kg^–1) contents than the others.  The Fe content of Ae. umbellulata was similar to those of Ae. comosa and Ae. markgrafii but higher than those of Ae. tauschii and common wheat.  Aegilops umbellulata showed a higher Zn content than Ae. tauschii, Ae. comosa, and common wheat, but a lower content than Ae. markgrafii.  Furthermore, Ae. umbellulata had the highest proportion of γ-gliadin among all the species investigated (Ae. umbellulata vs. other species=mean 72.11% vs. 49.37%; range: 55.33–86.99% vs. 29.60–67.91%).  These results demonstrated that Ae. umbellulata exhibits great diversity in the investigated traits, so it can provide a potential gene pool for the genetic improvement of these traits in wheat.     

TIMP2 promotes intramuscular fat deposition by regulating the extracellular matrix in chicken

The interaction between myocytes and intramuscular adipocytes is a hot scientific topic.  Using a co-culture system, this study aims to investigate the regulation of intramuscular fat deposition in chicken muscle tissue through the interaction between myocyte and adipocyte and identify important intermediary regulatory factors.  Our proteomics data showed that the protein expression of tissue inhibitor of metalloproteinases 2 (TIMP2) increased significantly in the culture medium of the co-culture system, and the content of lipid droplets was more in the co-culture intramuscular adipocytes.  In addition, TIMP2 was significantly upregulated (P<0.01) in muscle tissue of individuals with high intramuscular fat content.  Weighted gene co-expression network analysis revealed that TIMP2 was mainly involved in the extracellular matrix receptor interaction signaling pathway and its expression was significantly correlated with triglyceride, intramuscular fat, C14:0, C14:1, C16:0, C16:1, and C18:1n9C levels.  Additionally, TIMP2 was co-expressed with various representative genes related to lipid metabolism (such as ADIPOQ, SCD, ELOVL5, ELOVL7, and LPL), as well as certain genes involved in extracellular matrix receptor interaction (such as COL1A2, COL4A2, COL5A1, COL6A1, and COL6A3), which are also significantly upregulated (P<0.05 or P<0.01) in muscle tissue of individuals with high intramuscular fat content.  Our findings reveal that TIMP2 promotes intramuscular fat deposition in muscle tissue through the extracellular matrix receptor interaction signaling pathway.     

Ensiling vine tea (Ampelopsisgrossedentata) residue with Lactobacillusplantaruminoculant as an animal unconventional fodder

The study aimed to evaluate the application of silage fermentation in storing vine tea residue.  Dynamic of fermentation-related product, chemical component and bacterial community of silage with or without Lactobacillus plantarum F1 inoculant were analyzed.  The results showed that F1 treatment had a significant (P<0.05) impact on the lactic acid and ammoniacal nitrogen concentrations and pH value.  Total phenols were well preserved in both treatments.  After 30 days of ensiling, L. plantarum occupied the majority of Lactobacillus genus (more than 95%) in all silage samples.  Spearman revealed a positive (P<0.01) correlation between lactic acid content and Lactobacillus.  Overall, ensiling vine tea residue with L. plantarum can effectively preserve the nutritional attributes and total phenols, which offers a new insight into utilizing vine tea residue.     

OsMas1, a novel maspardin protein gene,confers tolerance to salt and drought stresses by regulating ABA signaling in rice

Drought and salt stresses, the major environmental abiotic stresses in agriculture worldwide, affect plant growth, crop productivity, and quality. Therefore, developing crops with higher drought and salt tolerance is highly desirable. This study reported the isolation, biological function, and molecular characterization of a novel maspardin gene, OsMas1, from rice. The OsMas1 protein was localized to the cytoplasm. The expression levels of OsMas1 were up-regulated under mannitol, PEG6000, NaCl, ...     

TBHQ对鸡舍PM2.5诱导鸡胚肺组织细胞焦亡、坏死和炎症损伤的影响

【目的】探讨特丁基对苯二酚(tert-Butylhydroquinone,TBHQ)对鸡舍细颗粒物(fine particulate matter,PM_2.5)诱导鸡胚肺损伤的缓解作用及机制,为预防和缓解鸡舍PM_2.5污染引起的鸡呼吸道健康问题提供理论依据。【方法】选用14日龄鸡胚作为研究对象,首先建立鸡舍PM_2.5诱导鸡胚肺组织损伤模型,再利用鸡胚肺损伤模型研究TBHQ的缓解作用。在建立鸡舍PM_2.5诱导鸡胚肺组织损伤模型试验中,选取不同浓度的PM_2.5(0、0.25、0.5、1 mg·mL^-1)在14日龄鸡胚卵白处注射,5 d后,观察鸡胚存活率以及鸡胚肺组织形态,选取合适的PM_2.5处理浓度(0.25 mg·mL^-1),建立鸡胚肺损伤模型。在TBHQ对PM_2.5诱导鸡胚肺损伤的影响试验中,将14日龄鸡胚分为对照组(生理盐水)、PM_2.5组(0.25 mg·mL     

供核细胞对绵羊体细胞克隆效率的影响

【目的】在制作克隆胚胎时,供核细胞直接制约着重构胚的融合数量和发育潜力。研究供核细胞对绵羊体细胞对克隆效率的影响。【方法】从供核细胞的静置时间,研究传代次数与周期处理,供核细胞不同克隆株,不同羊源细胞等,以重构胚融合率和囊胚发育率为检测指标,判定单因素供核细胞对克隆胚胎的影响。【结果】在供核细胞静置时间方面,供核细胞静置15~30 min内完成重构胚制作的融合率极显著高于静置2 h左右的供核细胞组(90.10% vs 78.84%)(P< 0. 01),但囊胚率差异不显著(15.58%vs 14.65%)(P＞0.05);在供核细胞传代次数(d1~d3)和汇合期生长时间方面(24 and 48 h ),各组的融合率差异不显著(70.37%、76.03%、71.92% vs 72.97%)(P＞0.05),但囊胚率有增高的趋势(5.96%、9.06%、15.85% vs 20.16%);在同一供核细胞不同克隆株方面,供核细胞对融合率和囊胚率存在显著(P<0.05)或极显著(P<0.01)的影响;在不同个体方面,供核细胞株对融合率和囊胚率存在极显著的影响(P<0.01)。【结论】15~30 min内的静置供核细胞、传代3次并延长汇合期细胞生长时间(48 h),多选细胞株更有利于克隆胚的制作。     

Effects of exogenous paclobutrazol and sampling time on the efficiency of in vitro embryo rescue in the breeding of new seedless grape varieties

Embryo rescue technology plays an important role in seedless grape breeding.  However, the efficiency of embryo rescue, including the embryo formation, germination, and seedling rates, is closely related to the parental genotypes, degree of abortion, growth medium, and plant growth regulators.  In this study, we investigated the effects of different concentrations of paclobutrazol (PAC), a plant growth regulator, and embryo collection times on the embryo formation, germination, and seedling rates for different hybrid combinations of grape breeding varieties used for their aroma and cold-resistance traits.  The results showed that the different PAC concentrations had varying impacts on the development of ovules and embryos from the different grape varieties.  The embryo formation rates of the ‘Sultanina Rose’בBeibinghong’ and ‘Kunxiang Seedless’בTaishan-2’ crosses were the highest under the 5.1 μmol L^–1 PAC treatment.  The 1.0 μmol L^–1 PAC treatment was optimal for the germination and seedling development of the ‘Sultanina Rose’בBeibinghong’ embryos, whereas the 0.2 μmol L^–1 PAC treatment induced the highest germination rate for the ‘Sultanina Rose’בKunxiang Seedless’ cross.  The optimal sampling times for each cross varied as 39 d after pollination (DAP) for the ‘Flame Seedless’בMuscat Hamburg’ cross, 46 DAP for the ‘Kunxiang Seedless’בBeibinghong’ cross, and 41 DAP for the ‘Ruby Seedless’בBeibinghong’ and ‘Fantasy Seedless’בShuangyou’ crosses.  Moreover, the medium modified with 0.5 g L^–1 of indole-3-butyric acid allowed the malformed seedlings to develop into plantlets and achieve larger progenies.  This study provides a useful basis for further studies into grape embryo rescue and could improve breeding efforts for new seedless grape varieties.     

甘加藏羊发情周期和乏情期HPO轴中THRβ mRNA和蛋白的表达分布

甲状腺激素(TH)通过与其靶细胞受体特异性结合发挥其生物学效能。为阐明松果体、下丘脑-垂体-卵巢轴(Hypothalamic-pituitary-ovary axis, HPOA)甲状腺激素受体β(Thyroid hormone receptor β, THRβ)基因和蛋白的表达及分布对季节性繁殖动物甘加藏羊(Ovis aries)生殖活动的调节。本研究以处于发情周期和乏情期的甘加藏羊为研究对象,应用RT-qPCR、Western blot 和免疫组织化学方法检测和分析了松果体、HPO轴中THRβ mRNA及其蛋白的表达和分布。结果显示,THRβ mRNA及其蛋白在松果体和HPO轴组织中均有表达和分布。在松果体中,THRβ mRNA及其蛋白的表达量均在乏情期最高,显著(P<0.05)高于发情周期;在下丘脑中,THRβ mRNA表达量在发情后期显著(P<0.05)高于其他时期,蛋白表达量在间情期显著(P<0.05)高于其他时期;在垂体中,THRβ mRNA及其蛋白的表达量在间情期显著(P<0.05)高于其他时期;在卵巢中,THRβ mRNA及其蛋白的表达量在发情后期显著(P<0.05)高于其他时期。免疫组织化学结果显示:THRβ免疫阳性产物主要分布在松果体细胞的细胞浆,下丘脑的神经胶质细胞、大神经元胞体和椎体细胞胞浆,腺垂体的嗜酸性和嗜碱性细胞胞浆,卵巢的颗粒细胞胞浆、卵泡内膜细胞及黄体细胞。甘加藏羊发情周期和乏情期松果体、HPOA组织中THRβ mRNA和蛋白的差异性表达,表明THRβ参与调控甘加藏羊的生殖活动。