春季低温对小麦颖果发育的影响

为了探明春季低温（倒春寒）导致小麦减产的细胞学机理,以扬麦15为材料,在小麦幼穗处于雌雄蕊分化期至药隔期之间时,设置-3 ℃低温处理,通过树脂半薄切片对颖果不同发育时期的形态结构进行观察。结果表明：（1）在颖果发育早期,低温促进了颖果的长度生长,抑制了宽度生长;与对照相比,低温处理组小麦颖果发育进程缩短;（2）低温处理组颖果果皮发育早,中果皮降解速度快;（3）低温处理增加了胚乳淀粉体的积累量,降低了蛋白体的积累量,发育后期胚乳充实度显著低于对照组;（4）与对照相比,低温处理后颖果韧皮部面积和珠心突起传递细胞面积增大。以上结果表明,春季低温处理更有利于养分运输组织的发育,使得灌浆时间缩短,最终导致淀粉积累量增加及颖果早熟。     

新疆春小麦育成品种耐热性评价

为筛选出耐热性好的小麦种质材料,通过开花期至成熟期人工模拟高温胁迫环境,以千粒重热感指数为主要评价指标,评价了新疆近30年来审定的春小麦品种的相对耐热性,并分析了高温胁迫对小麦籽粒蛋白质、湿面筋含量的影响。结果表明,与自然生长相比,高温胁迫条件下新疆春小麦育成品种的千粒重、籽粒宽度的变化均达到了极显著水平（P<0.01）,籽粒长度变化不显著(P>0.05),不同品种间耐热性存在很大差异。综合三年千粒重热感指数（HSI）分析,耐热性相对较好的品种有17个,连续三年HSI＜1的品种有11个,其中新春37号、新春2号、新春38号在高温胁迫条下千粒重变化较小,产量较稳定,为强耐热品种;对高温敏感品种有26个,连续三年HSI≥1的品种有13个,其中新春13号、新春18号、新春33号耐热性相对较弱。高温胁迫影响小麦籽粒的品质,其中13.95%的品种蛋白质含量降低,6.98%的品种湿面筋含量降低,其他品种高温胁迫后籽粒蛋白质、湿面筋含量均较自然生长有所提高。     

Roles of protein phosphatase 4 in down-regulation of eNOS Ser633 phosphorylation induced by palmitic acid in human umbilical vein endotheli?al cells

AIMTo investigate the roles of protein phosphatase 4 (PP4) in down-regulation of endothelial nitric oxide synthase (eNOS) Ser633 phosphorylation induced by palmitic acid (PA). METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with PA at 25 μmol/L, 50 μmol/L, 100 μmol/L and 200μmol/L for 36 h, or treated with PA at 100 μmol/L for 12 h, 24 h, 36 h and 48 h. Protein phosphatase 2A (PP2A) family inhibitor fostriecin (FST, 20 nmol/L) or okadaic acid (OA, 5 nmol/L) was selected to pretreat the HUVECs for 30 min. Protein phosphatase 4 catalytic subunit (PP4c) siRNA or protein phosphatase 2A catalytic subunit (PP2Ac) siRNA was transfected into the HUVECs. The protein expression levels of of eNOS, PP4c and PP2Ac, as well as the level of eNOS Ser633 phosphorylation, were detected by Western blot. The intracellular nitric oxide (NO) content was measured by DAF-FM DA. RESULTS(1) Compared with control group, the levels of eNOS Ser633 phosphorylation were decreased in PA groups in which the HUVECs were treated with 25 μmol/L, 50 μmol/L, 100 μmol/L and 200 μmol/L PA for 36 h (P<0.05) and 100 μmol/L PA for 24 h, 36 h and 48 h (P<0.05). No significant difference in the level of total eNOS protein expression among all the groups was observed. (2) Compared with control group, both FST and OA pretreatment reversed the reduction of eNOS Ser633 phosphorylation (P<0.05) and the decrease in intracellular NO content (P<0.05) induced by PA. No significant difference in the level of total eNOS protein expression among all the groups was observed. (3) Compared with si-Control group, the PP4c protein expression was significantly reduced (P<0.05), while the level of eNOS Ser633 phosphorylation was significantly increased in si-PP4c group (P<0.05). Although the levels of PP2Ac protein expression declined significantly (P<0.05), the level of eNOS Ser633 phosphorylation remained unchanged in si-PP2Ac group. No significant differencein the level of total eNOS protein expression among all the groups was found. CONCLUSION PA significantly reduces the level of eNOS Ser633 phosphorylation and the content of NO in the HUVECs, which may be due to PA inducing the activation of the PP2A family member PP4 rather than PP2A.     

胡麻脂肪酸去饱和酶基因(fads)差异表达分析

为了了解fad基因在胡麻蒴果发育过程中对不饱和脂肪酸的调控,对高、中、低三个不同亚麻酸(C18:3)含量的胡麻品种(’CDC Gold’,‘内亚7号’,’Linola’)进行了不同时期的品质测定,以及脂肪酸去饱和酶2a基因(fad2a)、脂肪酸去饱和酶2b基因(fad2b)、脂肪酸去饱和酶2c基因(fad2c)、脂肪酸去饱和酶3a基因(fad3a)、脂肪酸去饱和酶3b基因(fad3b)的qRT-PCR定量分析。结果表明,随着蒴果成熟,可溶性糖含量呈降低趋势,粗脂肪与粗蛋白不断积累,且差异显著(p<0.05)。fad2a基因、fad3a基因以及fad3b基因在各个时期中的表达符合正态分布。以0 d的蒴果为对照,在胡麻种子形成过程中,‘内亚7号’的三个基因在5 d和15 d的表达量迅速增加,到30 d时急剧减少,15 d的fad2a基因表达量为5.23倍,fad3a基因表达量是fad2a基因表达量的14.52倍,fad3b基因的表达量是fad2a基因表达量的16.14倍,表明这三个基因参与不饱和脂肪酸积累过程。在低亚麻酸含量品种‘Linola’30 d中,fad3a基因是fad2a基因表达量的52.71倍,fad3b呈下调趋势;在高亚麻酸含量品种‘CDCGold’30d中,fad3a基因与fad2a基因的表达量均呈下调趋势,fad3b的表达量为3.92倍;在中等亚麻酸含量品种‘内亚7号’中,fad2a基因表达量降低了0.31倍,fad3a基因是fad3b基因表达量的1.87倍。fad2b基因、fad2c基因熔解曲线不稳定,峰值低,可以在后续试验中继续探索。     

壤质土叶面喷施不同养分对强筋小麦产量和蛋白质组分的影响

在壤质土条件下,不同养分叶面喷施对强筋小麦的株高、成穗数影响不显著;叶面喷洒0.1%MnSO4、0.05%(NH 4)2M oO2和0.3%KH 2PO4、2%CO(NH 2)2等能提高强筋小麦的千粒重和产量。喷洒2%CO(NH 2)2和0.1%M nSO4有利于蛋白质和蛋白组分的提高。     

不同大豆品种籽粒体积、含水量、脂肪和蛋白质积累动态分析

采用来自辽宁、吉林、黑龙江三地的成熟期不同的三个大豆品种,研究其品种间籽粒体积积累、含水量变化、脂肪和蛋白质的积累动态以及各个过程的关系并比较出各品种间的异同.结果是:在籽粒从开始鼓粒到成熟期间各品种籽粒体积都是先鼓胀到一个最高值然后迅速回落.此期间的籽粒含水量都一直在下降,从开始鼓粒到体积最大期间含水量下降缓慢,而在体积达最大值后到成熟期间含水量下降迅速,很快接近稳定值.各品种脂肪积累总体上是先稳定上升,在接近成熟时略有下降.蛋白质的积累同样是缓慢上升至接近成熟时稳中有降.各品种在这四个指标积累过程中除含水量变化曲线基本无明显差别外,另三个指标变化曲线都有一些各自的特点.四个指标总体平均数之间的相关系数各不相同.     

Effect of dietary protein:energy ratio on intake, growth and metabolism of juvenile green abalone Haliotis fulgens

Juvenile green abalone Haliotis rufescens were grown under laboratory conditions at 21±1 °C and fed formulated diets consisting of different protein:energy ratios (mg protein/kcal), 62, 74, 85, 100, 108, for 60 days. The level of crude protein ranged from approximately 26% to 44% while the energy content remained constant at about 4.1 kcal g⁻¹. Growth ranged from 3.63 to 12.33 mg day⁻¹. The growth of abalone fed the 100 and 108 diets was significantly greater than that of each of the other diets. Protein efficiency ratio increased as the dietary protein content increased except for the T108 diet (44% crude protein). Abalone apparently consume food to satisfy an energy requirement. Caloric expenditure due to metabolism was estimated for abalone fed diets with protein ratios of 62, 85, 100. Energy loss due to respiration did not vary appreciably among abalone fed the different diets. The proportional distribution of dietary energy into fecal, digestible, growth, and metabolic energy was estimated for abalone fed these diets. Apparent dry matter digestibility was among the lowest for abalone fed the 100 P:E diet, but growth of abalone fed this diet was significantly higher than that of each of the other treatments except the 108 diet. Unexplained energy loss to achieve balance ranged from 7% to 28.5%, some of which is probably due to differential mucus and ammonia production. Results suggest a potential for the reduction of both dietary protein and lipid without causing any adverse effects on the growth response.     

副溶血弧菌的外膜蛋白及其抗原性研究↑（*）

本文对１３株不同来源的副溶血弧菌的外膜蛋白及其抗原性进行了比较研究。１３株副溶血弧菌的外膜蛋白有相似的ＳＤＳ－ＰＡＧＥ图谱。大多数菌株有五条主要的蛋白质，其大致分子量分别为：ａ、６９ｋＤａ；ｂ、６３ｋＤａ；ｃ、４０ｋＤａ；ｄ、３０ｋＤａ；ｅ、２８ｋＤａ。其中蛋白质ｂ是所有菌株共有的。与吸附后的兔抗副溶血弧菌血清Ｗｅｓｔｅｒｎ印迹法结果显示抗血清与多数副溶血弧菌菌株的外膜蛋白有一条共同的免疫反应带，其大致分子量为４４ｋＤａ。     

Dopamine modulates the physiological response of the tiger shrimp Penaeus monodon

Levels of glucose, lactate, pO₂, pCO₂, HCO₃⁻, TCO₂, Na⁺, K⁺, Cl⁻, protein, and oxyhemocyanin in the hemolymph and its osmolality and pH were measured when tiger shrimp, Penaeus monodon (13.5 ± 1.5 g body weight), were individually injected with saline or dopamine at 10^− 8, 10^− 7, or 10^− 6 mol shrimp^− 1. Results showed that hemolymph glucose, lactate, pCO₂, HCO₃⁻, and TCO₂ values increased from 2 to 4 h; hemolymph osmolality, Na⁺, and total protein had increased at 2 h; and hemolymph K⁺ decreased from 2 to 8 h after the dopamine injection. All physiological parameters returned to the control values 4–16 h after receiving dopamine. The dopamine injection also significantly decreased the oxyhemocyanin/protein ratio of P. monodon which occurred at 2 h, resulting from an elevation of hemolymph protein and a slight decrease of oxyhemocyanin. These results suggest that stress-inducing dopamine caused a transient period of modulation of energy metabolism, osmoregulation, respiration, and the acid–base balance in P. monodon in adapting to this environmental stress.     

Seminal plasma proteins of Atlantic halibut (Hippoglossus hippoglossus L.)

Protein content and properties in the seminal plasma of Atlantic halibut (Hippoglossus hippoglossus) were assayed using spectrophotometric and electrophoretic methods. The protein concentration ranged from 6.4 ± 3.1 to 19.4 ± 3.4 mg ml⁻¹ and anti-proteolytic activity from 585.2 ± 104.6 to 2912.4 ± 367.4 U l^−l. A high correlation between anti-proteolytic activity and protein concentration (r = 0.95), and between sperm concentration and osmolality was found (r = 0.92). There was a significant decrease in anti-proteolytic activity from the first to the second sampling, but not in protein concentration. Anti-proteolytic activity and protein concentration were significantly affected by variations in individual males. Electrophoresis revealed four anti-proteolytic bands and individual differences in bands of proteolytic activity, which were subsequently characterized as metalloproteases and serine proteases.