MdMYB1转录因子调控红星苹果果实着色的计算机模拟分析及表达验证

 从‘红星’苹果(Malus domestica‘Delicious’) 果实中克隆获得了MdMYB1基因, 通过生物信息学分析( in silico analysis) 和活体细胞融合蛋白荧光观察, 确定其编码蛋白定位于细胞核。同时, 克隆了MdDFR和MdUFGT基因的启动子, 模拟分析表明2个基因的启动子序列中含有MYB结合的顺式作用元件。为了探讨MdMYB1转录因子是否调控MdDFR和MdUFGT基因的表达, 对不同光照条件下果皮花青素含量和基因表达进行了检测, 结果表明光照能够诱导花青素积累, 并迅速启动3个基因表达, 且3个基因表现出高度相似的表达模式, 表明MdMYB1转录因子可能直接调控MdDFR和MdUFGT基因的表达。     

南亚热带李新品种‘华蜜大蜜李’

 ‘华蜜大蜜李’是从‘三华李’中选育出来的优良新品种, 果实近圆形, 平均单果质量51.5 g, 可溶性固形物含量9%～11% , 酸甜味浓, 肉质软溶, 丰产稳产, 是‘三华李’中的大果品种, 适合于南亚热带山区栽培。在广东6月中下旬果实红熟。     

Effects of carvedilol on murine viral myocarditis

AIM: To observe the effects of carvedilol on murine viral myocarditis model. METHODS: A total of 188 inbred male BALB/c mice of 4-6 weeks were divided into 4 groups: myocarditis group (group C, n=60), metoprolol treatment group (group M, n=60), carvedilol treatment group (group K, n=60), control group (group B, n=8). Myocardial histopathololgic changes were observed. The concentrations of cardiac troponin I (cTn-I) were detected by chemiluminescence immunoassay (CLIA). Western blotting was performed to analyze the contents of phosphorylated p38MAPK in myocardium. RESULTS: Metropolol and carvedilol lightened myocardial histopathololgic changes at acute stage, decreased cTn-I concentrations and myocardial phosphorylated p38MAPK value compared with myocarditis group. Treatment with carvedilol was more effective than treated with metropolol on those indexes. CONCLUSION: Carvedilol protects against viral myocarditis by inhibition of p38MAPK signal transduction pathway through blockade of β1 and β2 adrenergic receptors.     

Role of GPR40 mediates the effects of FFAs on lipoapoptosis in mouse β-cell line NIT-1

AIM: To evaluate the role of G protein-coupled receptor 40 (GPR40) mediates the effects of free fatty acids (FFAs) on lipoapoptosis in mouse β-cell line NIT-1 and the mechanisms involved in this process.METHODS: NIT-1 cells were supplemented with palmitate (500 μmol/L) or oleate (500 μmol/L) for 48 h, then apoptosis of the cells was determined by the methods of Hoechst 33342, TUNEL and flow cytometry (Annexin V/PI). The small interfering RNA technique was used to inhibit the expression of GPR40 in NIT-1 cell. The mock, control siRNA and GPR40 siRNA transfected cells were either supplemented with palmitate (500 μmol/L) or co-incubated with palmitate and oleate (500 μmol/L for each) for 48 h. The percentages of apoptotic cells were quantified. The expression of p-c-Jun, Bcl-2 and Bax were detected by Western blotting.RESULTS: Palmitate induced β cell lipoapoptosis, whereas oleate inhibited NIT-1 cells from palmitate-induced lipoapoptosis. No significant difference of the percentages of apoptotic cells was indicated among the mock, control siRNA and GPR40 siRNA transfected cells treated with palmitate (P>0.05). However, after co-incubated with palmitate and oleate (500 μmol/L for each) for 48 h, the percentage of apoptotic cells in GPR40 siRNA transfected cells was greater than that in mock (P<0.05), while the expression of p-c-Jun was decreased. The expressions of Bcl-2 and Bax were not affected.CONCLUSION: Palmitate induced β cell lipoapoptosis might not be mediated through GPR40, whereas oleate inhibits NIT-1 cells from palmitate-induced lipoapoptosis, which is mediated at least in part through GPR40, the change of c-Jun expression may play an role in this process, suggesting that GPR40 might be implicated in the control of β cell mass plasticity and GPR40 probably provides a link between obesity and type 2 diabetes.     

黄瓜游离小孢子培养诱导成胚和植株再生

 以10个不同基因型黄瓜为试材进行游离小孢子培养,通过对成胚条件的系统研究,从‘7447’和‘Poinsett97’中获得了子叶形胚和再生植株。研究结果表明：基因型和小孢子发育时期是限制黄瓜游离小孢子成胚的关键因子。不同品种间胚状体产量差异显著,每皿产胚1.5～33.4个。单核靠边期是进行黄瓜游离小孢子培养的最佳时期。低温预处理有利于胚状体的诱导,4 ℃预处理2～4 d为宜,以处理2 d时胚状体产量最高。外源激素在诱导胚状体时并非必需,但低浓度的外源激素（0.5 mg·L^-1 2,4－D、0.2 mg·L^-1 6－BA）更能促进小孢子成胚。NLN和B5两种基础培养基在诱导胚状体上无显著差异。子叶形胚易分化成苗,而其它类型的胚状体不能获得再生植株。     

Nontypeable haemophilus influenzae induces IL-8 expression in alveolar epithelial cells in a p38 MAPK and NF-κB dependent manner

AIM:To investigate the key molecular mechanism of inflammatory response in alveolar epithelial cells induced by nontypeable haemophilus influenzae (NTHi). METHODS: A549 cells were co-cultured with NTHi (multiplicity of infection, MOI: 10) and harvested 15 min and 30 min after stimulation. The phosphorylation of p38 mitogen activated protein kinase (p38 MAPK) in A549 cells was detected by Western blotting. The intracellular expression of nuclear factor-κB (NF-κB) p65 was examined by flow cytometry 4 h after stimulation. A549 cells were preincubated with p38 inhibitor (SB203580) or NF-κB inhibitor (PDTC) for 1 h and then stimulated with NTHi for 24 h. The level of interleukin 8 (IL-8) in the supernatants was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The phosphorylation of p38 MAPK was rapidly induced by NTHi stimulation. The expression of NF-κB p65 in A549 cells after NTHi stimulation was significantly up-regulated compared with control group (P<0.05). The level of IL-8 in the supernatants was increased 24 h after bacterial stimulation compared with control group (P<0.05). Blockage of p38 MAPK or NF-κB remarkably decreased IL-8 secretion in A549 cells (P<0.05). CONCLUSION:NTHi induces inflammatory response in alveolar epithelial cells in a p38 MAPK and NF-κB dependent manner.     

Protective effect of rAAV2-NTF2 on blood-retinal barrier damage in diabetic rats

AIM: To explore the effect of rAAV2-NTF2 on the blood-retinal barrier damage in early stage diabetic retinopathy. METHODS: Retinal vasculature was observed by Evans blue. NTF2 gene was cloned into adeno-associated virus vector pSNAV. The recombinant pSNAV-NTF2 was transfected into BHK cells. After purification, high-titer rAAV2-NTF2. rAAV2-NTF2 at dose of 4 μL (titer 1.0×1012) were injected into left eyes and rAAV2-EGFP at the same does and titer were injected into the right eyes of 36 rats. After 1 month, diabetes mellitus were induced by STZ. One month after onset of diabetes, EB at a dose of 45 mg/kg was intravenously injected into the rats. Two hours later, both eyes were enucleated immediately after perfusion of 1% PFA-citric acid buffer solution. The retinas were then dissected away and placed in formamide to extract the dye. The concentration of dye was measured by spectrophotometer. RESULTS: Evans blue was contained in normal retinal vessels without leakage, with a very low level of background fluorescence. The vessels staining of diabetic rats’ retina showed increasing fluorescence, indicating the retina-blood barrier damage. Dye concentration, representing the degree of the BRB injury, was higher in retina of 1 month diabetic rats than that in normal rats (4.67 times, P<0.01), indicating retina-blood barrier break-down. Diabetic rats with rAAV2-NTF2 intravitreal injection showed decreased BRB breakdown (P<0.05). CONCLUSION: High expression of NTF-2 decreases the BRB dysfunction in DM rats.     

Adiponectin protects human umbilical vein endothelial cells from lipid peroxidation

AIM:To study the effect of adiponectin (APN) on lipid peroxidation in human umbilical vein endothelial cells (HUVECs) induced by hydrogen peroxide (H2O2) in vitro.METHODS:The effect of H2O2 on apoptosis was measured by flow cytometry with Annexin V-FITC labeling.The concentration of malonaldehyde (MDA) in HUVECs was detected by thiobarbituric acid (TBA) method.The activities of superoxide dismutase (SOD) and catalase (CAT) were measured by colorimetric assay.The scavenging rate on superoxide anion radicals in xanthine oxidase system and OH radicals produced by Fenton reaction were also tested.RESULTS:APN significantly inhibited H2O2-induced apoptosis.H2O2 increased MDA production and reduced the activities of SOD and CAT, which were inhibited by APN.APN did not alter the activities of SOD and CAT in normal condition.APN dose-dependently decreased the superoxide anion radicals, with the scavenging rate of 11.9%, 21.4%, 36.9%,respectively, and scavenged OH radicals.CONCLUSION:APN inhibits apoptosis and protects endothelial cells against lipid peroxidation insult by scavenging the free radicals.     

Functions of wild stathmin 1 and the C terminal mutant

AIM: To illustrate the effects of overexpression of stathmin 1 on melanocyte growth and the relationship between C terminal motif and stathmin 1 function.METHODS: The overexpression vector and C terminal mutant coding vector were constructed. The vectors were transfected into melanocytes by Lipofectamine 2000. MTT and FCM were used to inspect the cell growth, Western blotting was a tool in caspase-3 measurement, and spectrophotography was used to detect the melanin products and tyrosinase activity.RESULTS: The vectors of overexpression and mutation were constructed and transfected into melanocytes successfully. Both of them inhibited the melanocyte growth, induced apoptosis, and decreased the melanin products and tyrosinase activity.CONCLUSION: Overexpression of stathmin 1 inhibits melanocyte growth, melanin products and tyrosinase activity. The change of C terminal motif could not affect the role of stathmin 1 in melanocyte markedly.