The role of MC1R gene in buffalo coat color

Melanocortin-1 receptor (MC1R) plays a major role in pigmentation in many species. To investigate if the MC1R gene is associated with coat color in water buffalo, the coding region of MC1R gene of 216 buffalo samples was sequenced, which included 49 black river buffalo (Murrah and Nili-Ravi), 136 swamp buffalo (Dehong, Diandongnan, Dechang, Guizhou, and Xilin) with white and gray body, and 31 hybrid offspring of river buffalo Nili-Ravi (or Murrah) and swamp buffalo. Among the three variation sites found, SNP684 was synonymous, while SNP310 and SNP384 were nonsynonymous, leading to p.S104G and p.I128M changes, respectively. Only Individuals carrying homozygote E-BR/E-BR were black. The genotype and phenotype analysis of the hybrid offspring of black river buffalo and gray swamp buffalo further revealed that the river buffalo type allele E-BR or the allele carrying the amino acid p.104S was important for the full function of MC1R. The in silico functional analysis showed that the amino acid substitutions p.G104S and p.M128I had significant impact on the function of MC1R. Above results indicate that the allele E-BR or the allele carrying the amino acid p.104S was associated with the black coat color in buffalo.

In vitro construction of a recombinant human embryonic brain-derived neurotrophin-4 gene and pEGFP-N1 vector

BACKGROUND: Neurotrophin-4 (NT-4) can promote neuronal growth, development, differentiation, maturation, and survival. NT-4 can also improve recovery and regeneration of injured neurons, but cannot pass through the blood-brain barrier, which limits its ac

17种植物中蛋白质提取物的抗HIV-1活性

以化合物对ＨＩＶ１诱导Ｃ８１６６细胞形成合胞体的抑制实验和化合物对ＨＩＶ１感染细胞的保护实验作为初筛方法，筛选了来源于７科１７种植物的４７个样品，其中８个样品经测定是核糖体失活蛋白（ＲＩＰｓ），其余为粗提蛋白。进而测定了初筛有抗ＨＩＶ活性的化合物对共培养、急性和慢性感染的ＨＩＶ１ｐ２４抗原表达水平的影响，用间接荧光染色检测这些化合物对ＨＩＶ抗原阳性细胞率的影响，以确证其抗ＨＩＶ活性。天花粉蛋白（ＴＣＳ）、南方栝楼蛋白峰Ⅴ、南方栝楼蛋白峰Ⅵ均显著地抑制合胞体的形成；巴Ⅱ、丝瓜子蛋白、油瓜根蛋白、木盍藤子蛋白有一定的抑制作用。老鼠拖瓜蛋白、大叶木鳖子根蛋白、西双版纳根Ⅱ等粗提蛋白有显著的抑制作用。ＲＩＰｓ不能保护ＨＩＶ１感染细胞的死亡。ＴＣＳ显著地抑制了ＨＩＶ１急性感染中ｐ２４抗原的表达，减少了ＨＩＶ抗原阳性细胞数，但它们均不影响共培养细胞融合、ＨＩＶ１慢性感染中ｐ２４抗原表达水平。结果表明，除ＴＣＳ等已知ＲＩＰｓ外，还有一些新的ＲＩＰｓ具有不同程度的抗ＨＩＶ活性。

Prevalent positive epistasis in Escherichia coli and Saccharomyces cerevisiae metabolic networks

Epistasis refers to the interaction between genes. Although high-throughput epistasis data from model organisms are being generated and used to construct genetic networks(1-3), the extent to which genetic epistasis reflects biologically meaningful interactions remains unclear(4-6). We have addressed this question through in silico mapping of positive and negative epistatic interactions amongst biochemical reactions within the metabolic networks of Escherichia coli and Saccharomyces cerevisiae using flux balance analysis. We found that negative epistasis occurs mainly between nonessential reactions with overlapping functions, whereas positive epistasis usually involves essential reactions, is highly abundant and, unexpectedly, often occurs between reactions without overlapping functions. We offer mechanistic explanations of these findings and experimentally validate them for 61 S. cerevisiae gene pairs.

中国银额果蝇自然群体B染色体的分布

中国(台湾省外)银额果蝇自然群体中普遍存在Bs。结合前人报道提出,Bs频率的地理分布出现了由东向西和由南向北的规律性的依次升高趋势。这种跨越不同地理环境的区域性梯度变异与其宿主向大陆内地扩散的推论相符。Bs频率最高(87.7%)的是海南岛的孤立隔离群体。大部分群体含Bs的数目多,最多达14条,为标准染色体数目(2n=6)的2.3倍。同时依据该果蝇Bs频率的地理分布特点,将我国现生的银额果蝇划归为5个生态型群体,即沿海丘陵群体、高原型群体、岛屿型群体、山地型群体和峡谷群体等。

Effects of different levels of energy and protein sources on the growth performance, feeding, survival rate and the chemical body composition of juvenile Pacific white shrimp (Litopenaeus vannamei)

The present study was carried out in order to establish an economical effective diet for the pacific white shrimp in the southern part conditions of Iran. With the consideration of three dietary energy levels (E1=262, E2=312, E3=362 kcal 100 g-1 diet) and six ratios of fish meal (FM) to soybean meal (SBM) [(P1=100%FM+0%SBM, P2=80%FM+20%SBM, P3=60%FM+40%SBM, P4=40%FM+60%SBM, P5=20%FM+80%SBM, P6=0%FM+100%SBM)], 18 experimental diets (with 36% crude protein) were prepared. Completely randomized design was used to assign 54 polyethylene 300 litre round tanks provided by aeration and flow through water system and was stocked by 19 juvenile as 3 replicates to each treatment. Shrimps average weight was about 0.77 grams at the start. After 56 days culture period, maximum growth and nutritional performances were observed in the P6E1 treatment (containing 100% soybean meal and 262 kcal 100 g-1 diet) and P5E1 treatment (containing 80% soybean meal and 262 kcal 100 g-1 diet). Also the highest survival rate of the shrimps was observed in the P1E1, P1E2, P3E3 and P5E3 treatments. Additionally interactive effect of different protein ratios and energy levels had significant difference on body protein, fat, fiber and ash contents (P<0.05). Results of the present study suggest the possibility replacement of at least 80% of dietary fish meal by soybean meal in the diet of pacific white shrimp in the conditions of southern part of Iran.

Effects of Prenatal Exposure to a 50-Hz Magnetic Field on One-Trial Passive Avoidance Learning in 1-Day-Old Chicks

We investigated memory impairment in newly hatched chicks following in ovo exposure to a 50-Hz magnetic field (MF) of 2 mT (60 min/day) on embryonic days 12-18. Isolated and paired chicks were used to test the effect of stress during training, and memory retention was tested at 10, 30, and 120 min, following exposure to a bitter-tasting bead (100% methylanthranilate). Results showed that memory was intact at 10 min in both isolated and paired chicks with or without MF exposure. However, while isolated chicks had good memory retention levels at 30 and 120 min, those exposed to MF did not. The results suggest a potential disruption of memory formation following in ovo exposure to MF, with this effect only evident in the more stressed, isolated chicks. Bioelectromagnetics 31:150-155, 2010. (C) 2009 Wiley-Liss. Inc.

四种渗透性防冻剂在猕猴精子低温冷冻保存中对精子功能状态的影响

以冷冻精子的复苏运动度、荧光染料Hoechst 33258 检测的细胞膜完整率、异硫氰酸荧光素标记的 花生凝集素(FITC2PNA) 检测的顶体完整率作为精子功能状态的指标, 对甘油、二甲亚砜、乙二醇和丙二醇4 种常用渗透性防冻剂在猕猴精子冷冻保存过程中的作用进行了比较。结果表明: 冷冻保存精子的复苏运动度, 甘油(4713 ±517 %) 和乙二醇(4418 ±617 %) > 二甲亚砜(2219 ±019 %) > 丙二醇(0 ±0 %) ; 细胞膜完整 率, 甘油(5418 ±312 %) 和乙二醇(5410 ±617 %) > 二甲亚砜(3715 ±710 %) > 丙二醇(2813 ±615 %) ; 顶 体完整率, 甘油(8212 ±214 %) 和乙二醇(8214 ±214 %) > 二甲亚砜(6817 ±517 %) 和丙二醇(7213 ± 315 %) ( P < 0105) 。结果提示: 二甲亚砜和丙二醇, 尤其是丙二醇并不适合猕猴精子的冷冻保存; 而乙二醇具 有和甘油相似的保护作用, 是一种极具潜力的猕猴精子冷冻保存的渗透性防冻剂。

云南鱼类多样性和面临的危机

迄今共记载云南土著鱼类432种,占全国淡水鱼类总种数1023种的42.2%,显示云南是我国淡水鱼类多样性最为丰富的省区之一。全省大约有1/3的种类日趋减少或濒临绝灭,湖泊鱼类尤为突出,濒危种几乎达到2/3。

嗜酸热硫球菌染色质碱性蛋白的提取

先用甲醇固定, 再用稀盐酸抽提方法对嗜酸热硫球菌染色质碱性蛋白进行了提取, 并将它与小牛胸腺组蛋白进行了比较研究。所获蛋白在两种电泳系统中都显示三种主要成分, 其分子量均小于小牛胸腺组蛋白H4。三者中以分子量最大者含量最高, 碱性则以分子量最小者最强。图2参12

萤火虫的发光行为及其功能起源

下载PDF阅读器发光生物因其活体能自发荧光而倍受关注,萤火虫(鞘翅目:萤科)是被研究最多的发光生物,因为成虫发光在其性选择以及求偶交配中起着重要作用.由于萤火虫的发光是一个消耗能量(ATP),的化学反应过程,因而其发光在成虫之外的虫态也具有重要意义.本文就萤火虫成虫和幼虫的发光行为、功能意义进行了综述,并结合萤火虫的饲养观察对其卵和蛹的发光行为进行了描述,探讨了卵和蛹的形态阶段发光的生物学功能以及生物荧光的起源进化.这将有助于理解萤火虫及其它生物自发荧光的本质和起源进化过程.

Final report of the baseline data reconstruction for the Quality Assurance for Fish Marketing Project

A baseline survey for the project which had been conducted in 2009 had gaps that could not allow assessment of project performance in the outcome and impact indicators to be made. This study was, therefore, commissioned to reconstruct the baseline data, aligned to the impact and outcome indicators on the project logframe and results framework, against which project achievements could be assessed. The purpose and scope of the study was to reconstruct the baseline data and analysis describing the situation prior to QAFM Project inception, taking 2008 as the baseline year, which was aligned to the project logframe outcome and impact indicators; to collect data on current status to compare project outcome (and where possible impact) in improved fish handling sites in comparison with the baseline as well as with comparable non-improved fish landing sites as control group. The study was conducted through secondary data search from sources at NaFIRRI, DFR and ICEIDA. Field data collection was carried out using a sample survey covering 312 respondents including boat and gear owners, crew members, processors and traders at eight project and two control landing sites. Key Informant Interviews were conducted with DFOs and BMU leaders in the study districts and landing sites respectively.