Dog chromosome-specific paints reveal evolutionary inter- and intrachromosomal rearrangements in the American mink and human

Forty chromosome-specific paint probes of the domestic dog (Canis familiaris, 2n = 78) were used to delineate conserved segments on metaphase chromosomes of the American mink (Mustela vison, 2n = 30) by fluorescence in situ hybridisation. Half of the 38 canine autosomal probes each painted one pair of homologous segments in a diploid mink metaphase, whereas the other 19 dog probes each painted from two to five pairs of discrete segments. In total, 38 canine autosomal paints highlighted 71 pairs of conserved segments in the mink. These painting results allow us to establish a complete comparative chromosome map between the American mink and domestic dog. This map demonstrates that extensive chromosome rearrangements differentiate the karyotypes of the dog and American mink. The 38 dog autosomes could be reconstructed from the 14 autosomes of the American mink through at least 47 fissions, 25 chromosome fusions, and six inversions. Furthermore, comparison of the current dog/mink map with the published human/dog map discloses 23 cryptic intrachromosomal rearrangements in 10 regions of conserved synteny in the human and American mink genomes and thus further refined the human/mink comparative genome map. Copyright (C) 2000 S. Karger AG, Basel.

Phylogenetic implications of the 38 putative ancestral chromosome segments for four canid species

Chromosome homologies between the Japanese raccoon dog (Nectereutes procyonoides viverrinus, 2n = 39 + 2-4 B chromosomes) and domestic dog (Canis familiaris, 2n = 78) have been established by hybridizing a complete set of canine paint probes onto high-res

mtDNA Data Indicate a Single Origin for Dogs South of Yangtze River, Less Than 16,300 Years Ago, from Numerous Wolves

There is no generally accepted picture of where, when, and how the domestic dog originated. Previous studies of mitochondrial DNA (mtDNA) have failed to establish the time and precise place of origin because of lack of phylogenetic resolution in the so fa

Molecular cloning and expression characterization of ApoC-I in the orange-spotted grouper

Endogenous yolk nutrients are crucial for embryo and larval development in fish, but developmental behavior of the genes that control yolk utilization remains unknown. Apolipoproteins have been shown to play important roles in lipid transport and uptake through the circulation system. In this study, EcApoC-I, the first cloned ApoC-I in teleosts, has been screened from pituitary cDNA library of female orange-spotted grouper (Epinephelus coioides), and the deduced amino acid sequence shows 43.5% identity to one zebrafish (Danio rerio) hypothetical protein similar to ApoC-I, and 21.2%, 21.7%, 22.5%, 20%, and 22.5% identities to Apo C-I of human (Homo sapiens), house mouse (Mus musculus), common tree shrew (Tupaia glis), dog (Canis lupus familiaris) and hamadryas baboon (Papio hamadryas), respectively. Although the sequence identity is low, amphipathic alpha-helices with the potential to bind to lipid were predicted to exist in the EcApoC-I. RT-PCR analysis revealed that it was first transcribed in gastrula embryos and maintained a relatively stable expression level during the following embryogenesis. During embryonic and early larval development, a very high level of EcApoC-I expression was in the yolk syncytial layer, indicating that it plays a significant role in yolk degradation and transfers nutrition to the embryo and early larva. By the day 7 after hatching, EcApoC-I transcripts were observed in brain. In adult, EcApoC-I mRNA was detected abundantly in brain and gonad. In transitional gonads, the EcApoC-I expression is restricted to the germ cells. The data suggested that EcApoC-I might play an important role in brain and gonad morphogenesis and growth.

甘肃临夏盆地晚中新世鬣狗类群头骨的几何形态测量学及生态形态学分析

本文采用几何形态测量的方法对产自和政地区的鬣狗科Hyaenictitherium, Ictitherium, Adcrocuta和旁鬣狗科Dinocrocuta的材料进行研究，分析了这4个属保存完好的头骨标本的侧面形态。与东非大草原现生食肉动物的头骨整体形态分布的比较和分析表明，和政的鼬鬣狗(Ictitherium)和鬣型鼬鬣狗(Hyaenictitherium)的头骨形状分布介于现生斑鬣狗(Crocuta crocuta)、犬科猎狗(Lycaon pictus)和金豺(Canis aureus)之间，为二者似豺生态形态的解释提供了几何形态测量证据。再者，上述两属化石鬣狗的形状分布与现生斑鬣狗的幼年个体形状重叠，表明现生斑鬣狗头骨的发育机制可能是在鼬鬣狗祖先类型的异速生长规律基础上的持续发育，进而演化出现有的粗壮形态。此外，巨鬣狗(Dinocrocuta)和副鬣狗(Adcrocuta)的头骨形状与现生的斑鬣狗在几何形态测量空间内有普遍重叠的现象，指示了这些异时出现的种类具有相似的生态形态，因而可能占据相近的生态位。结果还显示巨鬣狗和斑鬣狗的幼年个体形状相近，以及两者从幼年到成年发育的形状变化过程也具有相似的规律。因而，巨鬣狗和斑鬣狗之间的趋同演化不仅表现在成年头骨的粗壮程度上，而且在幼年发育模式中也存在平行演化现象。现生发育学与行为生态学已经证实，相对其他大型食肉动物，现生斑鬣狗发育粗壮头骨形态的机制不是以增速生长，而是以延长发育期来实现的。由此推断，巨鬣狗的发育期有可能和现生鬣狗相当(35个月)，也可能由于具有相对粗壮和巨大的头骨形态，其发育期会延长些。当然，这个新解释仍需要更多的化石数据和发育研究来证实。

自养氨氧化混合种群特性和共存机理初步研究

组特殊自养氨氧化混合种群，表现：无机环境种群生长迅速、生物量高；在一个完全无机的自养生长环境中，不仅保持高氨氧化速率，并出现丰富的异养微生物种群；该种群置于异养、厌氧环境中，迅速表现出产氢特征。对于这样一个特殊的生态体系，研究其共生机理，以及联接这些种群之间的碳源和能源问题，将具有非常重要意义。我们拟从种群特征、细胞表面分泌产物、游离体系产物多糖、蛋白和脂肪酸方面开展研究。 第一部分，自养氨氧化混合种群的基本特征。采用氨氧化培养基，进行种群氨氧化特征研究；采用扫描电镜观察自养混合种群的微观特征；沉降、离心去除微生物种群，分析水相中的总有机碳、糖类等物质；利用LB培养基进行种群的分离、纯化，并采用DGGE手段对微生物种群结构进行分析。结果表明，接入菌种后（2/5000（V/V）），培养液中氨（200mg/L）在3－5天内快速降解；亚硝酸盐与氨氮变化呈负相关趋势，仅有少量硝酸盐含量（< 30mg/L）。氨氧化种群的生物量增长与氨氧化趋势一致，初始生物量7.75 mg/L(蛋白含量)，3-5天后生物量快速增长，并达到最高63.06 mg/L（蛋白含量）。电镜图片显示，种群外包裹一层粘液。离心除去菌体后，检测培养液总有机碳和糖的含量，同样表现出与生物量增长相似的特征，分别由初始的3.73、2.35 mg/L，3－5内天迅速增加，并分别达到最大值35.19、27.45 mg/L。经初步分离、纯化并对纯化菌株进行测序，获得了10株异养微生物分别为布鲁氏菌科苍白杆菌属、纤维单孢菌、类芽孢菌属、黄杆菌属、无色杆菌、鞘脂单胞菌、嗜麦芽寡养单胞菌、噬氢菌属、硫红球菌、假单胞菌；DGGE显示，约有20分条离带，我们对其中的两条优势条带进行切割回收测序，鉴定为欧洲亚硝化单胞菌（Nitrosomonas eur）。 第二部分：混合种群自养-异养菌共生的可能机制。在对微生物种群特征初步分析基础上，针对胞外糖类组分可能被微生物代谢分解，我们重点对微生物细胞蛋白质与糖类进行分析。采用超声结合RIPA裂解液裂解，SDS-PAGE电泳分析混合种群总蛋白种类，并通过氨基酸分析仪及红外光谱法分析氨基酸组成及蛋白红外特征。采用超声破碎结合反复冻融对细胞样品进行处理，提取液采用醇沉、Sevage脱氮白，凝胶过滤方法脱盐和分级分离。对提取物的糖分析包括：紫外扫描，红外光谱，核磁共振，单糖组成分析；扫描电镜观察菌群破裂现象。SDS-PAGE分析结果表明：氨氧化种群不同生长阶段都显示出42kD蛋白表达量很高，d4时42kD蛋白表达已经很强，4-7d内一直持续这种过量表达，直到d8后表达开始减弱。说明42kD蛋白可能与氨氧化密切相关。红外光谱分析显示：细胞提取物的特征峰分布在3427.42cm-1、1718.18 cm-1和1681.72 cm-1、1160.07和1086.74 cm-1，分别对应为OH、 C=O、C－O－C基团，表明具有蛋白的典型特征；氨基酸分析显示蛋白中的Gly,Asp,Ala,Glu含量相对较高。 提取物中胞外多糖分离谱图得到不均一组分，共得到6个收集峰；紫外扫描在201－213 nm处有多糖吸收峰，同样表明多糖成分不均一性；多糖红外光谱特征峰主要分别在3400.49 cm-1、2920.28 cm-1、1154.54和1087.52 cm-1，对应OH、－CH2－ or CH 、C－O－H or C－O－C等多糖特征基团；多糖提取物核磁共振1H d4.3～5.9之间出现强吸收峰，这是1H中，多糖存在的明显证据，1H NMR中，其中O-乙酰基的甲基上的氢信号为d1.1～1.3之间。糖肟全苯甲酸酯衍生物的HPLC测定中，得到单一的单糖峰，由于时间问题，还未进行更深入的试验；电镜图片显示，种群中的细胞有大量的破裂现象。 实验表明，自养氨氧化混合种群显示出快速的氨氧化速率，氨氧化过程生物量和有机质的增加明显。微生物种群包裹粘液层，并分离纯化出大量的异养菌；去除菌体后的游离培养液中存在有机质（包括多糖）说明无机自养生长体系中存在异养菌生长、繁殖的二次碳源；细胞提取物中蛋白条带数目多、种类丰富；细胞多糖提取物具有明显的多糖特征，以及单糖的存在。结合种群的显微特征和游离体系中的有机质的检测结果，我们认为，无机自养生长体系中，种群细胞生长过程中发生的破裂现象可能是导致大量的蛋白、多糖释放到游离胞外，并成为其他异养菌生长的碳源和氮源。这可能是自养体系中，大量异养菌共生的可能机制，至于是什么原因引起种群生长过程中产生的破裂现象，还有待下一步深入研究。 A group of mixed autotrophic ammonia oxidizing populations, having much biological characteristic tested by concerned personnel for pilot test: Performed rapid population growth and obtained high biomass in inorganic environment; Not only maintained a high rate of ammoxidation, promoted a wealth of heterotrophic microbial populations growth in a totally inorganic and autotrophic growth environment; Placed in heterotrophic and anaerobic environment,had the performance characteristics that could rapidly produce hydrogen.For such a special ecological system, Study its symbiotic mechanism and the connection between these populations of carbon and energy issues, will have a very important significance. We intended from the characteristics of the population, the secretion product of cell surface, free substance in the liquid medium like polysaccharide, protein and fatty acids carrying out research. Part I: The basic features of mixed autotrophic ammonia oxidizing populations . Use inorganic liquid medium, processed study for ammonia oxidation characteristics of the population; we used scanning electron microscopy to get micro-features of autotrophic ammonia oxidizing populations .The medium was carried out settlement and centrifugal then removed the microbial populations, after all of that we analysis the water phase for total organic carbon(TOC), carbohydrate and other substances; Solid ammonia oxidizing medium was adopted to separation and purification of population, DGGE means was for structure analysis of microbial population. The results showed that after the inoculum of bacteria (2 / 5000 (V / V)), ammonia in the culture medium (200 mg / L) was rapid degradation in 3-5 days; ammonia and nitrite have the negative correlation between changes in the trend, then only a small amount of nitrate content (<30mg / L). The biomass growth of ammoxidation population in line with the trend of ammonia oxidation, the initial volume of it was 7.75 mg / L (protein content), in 3-5 days upto 63.06 mg / L (protein content). Electron microscope image showed, the populations were wrapped in a layer of mucus, including the a large number ruptted micorbe , Centrifuge to remove bacteria, then detected the medium for total organic carbon and sugar content, result took on the same characteristics with biomass growth, that were from the initial 3.73、2.35 mg / L respectively, in 3-6 days achieved rapid increase in the maximum to 35.19、27.45 mg / L respectively. After initial separation、 purification ,then processed sequencing to strains purified and got the result that there were 10 heterotrophic microorganisms : Brucella Branch pale bacillus, Cellu lomonas, Bacillus species category, a Flavobacterium, colorless Bacteria, Aeromonas sheath fat, little support maltophilia Aeromonas, macrophages species hydrogen, sulphur-MI, Pseudomonas bacteria spores; DGGE display, there were 20 separation bands approximately. Part II: Mixed populations that autotrophic - heterotrophic bacteria symbiotic mechanism. On the basis of preliminary analysis of microbial population characteristics, aiming at extracellular carbohydrate components might be decomposition by microbial, we focused on microbial cell protein and carbohydrate analysis. Using ultrasound combined with RIPA lysis cracking the cells, SDS-PAGE electrophoresis analysis the total protein species of the population, and through the amino acid analyzer studied the compositions of amino acid and infrared spectroscopy analysis of a protein infrared characteristics. Using ultrasound combined with repeatedly freezing and thawing to treated the cell sample, then took the means that alcohol precipitation, deproteinization by Sevage, gel filtration aimed at desalination and grade separation to deal with the lysates . The extraction of sugar analysis included: UV scanning, IR, NMR, single-sugar composition analysis. SDS-PAGE analysis showed that: 42 kD protein expression was very high at different growth stages of mixed autotrophic ammonia oxidizing populations , on the fourth day, 42 kD protein expression had been very strong, 4-7d, it had continued this excessive expression, then started to weaken after 7 days. 42 kD protein that might be closely associated with ammonia oxidation. Infrared spectral analysis showed that: cell extracts with the characteristic that the peak distribution in 3427.42 cm-1、1718.18 cm-1 and 1681.72 cm-1、1160.07 cm-1 and 1086.74 cm-1 corresponding to OH、C = O、C-O-C Groups which had the typical characteristics of protein; and analysis showed that amino acids including Gly, Asp, Ala, Glu ,the content in the protein is relatively high. Exopolysaccharide in the extracts had the separation map that it was uneven, received a total of six collection peaks by the detection mode of phenol-sulphruic acid method ; ultraviolet scan in the 201-213 nm department had polysaccharide absorbing peak, the same ingredients that polysaccharide heterogeneity; infrared polysaccharide spectral characteristics of the main peak at 3400.49 cm-1, 2920.28 cm-1, 1154.54 and 1087.52 cm-1, corresponding OH,-CH2-or CH, C-O-H or C-O-C;and other characteristics of polysaccharide group; 1H NMR of polysaccharide extract appeared absorption peak between d4.3 ~5.9, which is the apparent evidence of polysaccharide, In 1H NMR, the hydrogen signal of one of O-acetyl was between 1.1 to 1.3. The determination of Sugar oxime whole benzoate derivatives by HPLC, there was a single-sugar peak, as a matter of time, yet more in-depth test. Summary: Mixed autotrophic ammonia oxidizing populations show us that it had the ability in ammonia oxidizing and it was great, organic matter and biomass increased significantly in the process of ammonia oxidation. Microbial populations was wrapped up slime layer, the phenomenon of cell breakdown obviously, and there were a lot of separation and purification of the heterotrophic bacteria; a lot of organic matter (including polysaccharides)remined in the medium that removal of cell indicated the inorganic system existed secondary carbon sources that could be used by the heterotrophic bacteria ; there were a large number proteins bands of cell extract, rich variety; cell extracts of polysaccharide had obvious characteristics of polysaccharide, and the existence evidence of single-sugar. Combined population of microscopic characteristics and free of organic matter in the test results, we believe that the health of inorganic system, population growth occurred in the course of the breakdown of the phenomenon is likely to lead to a lot of protein and polysaccharide released into the extracellular free, And other heterotrophic bacteria use them to the growth as carbon and nitrogen. This may be autotrophic system, the large number of heterotrophic bacteria symbiotic mechanism.