Avian comparative genomics: reciprocal chromosome painting between domestic chicken (Gallus gallus) and the stone curlew (Burhinus oedicnemus, Charadriiformes) - An atypical species with low diploid number

The chicken is the most extensively studied species in birds and thus constitutes an ideal reference for comparative genomics in birds. Comparative cytogenetic studies indicate that the chicken has retained many chromosome characters of the ancestral avia

Evolutionary implications of avian infectious Bronchitis Virus (AIBV) analysis

For developing efficient vaccines, it is essential to identify which amino acid changes are most important to the survival of the virus. We investigate the amino acid substitution features in the Avian Infectious Bronchitis Virus (AIBV) antigenic domain o

Relaxation of selective constraints on avian mitochondrial DNA following the degeneration of flight ability

The evolution of flight is the most important feature of birds, and this ability has helped them become one of the most successful groups of vertebrates. However, some species have independently lost their ability to fly. The degeneration of flight abilit

Secondary structural analysis of the mRNA regions encoding the hemagglutinin cleavage site basic amino acids of the avian influenza virus H5N1 subtype samples

Here we report the codon bias and the mRNA secondary structural features of the hemagglutinin (HA) cleavage site basic amino acid regions of avian influenza virus H5N1 subtypes. We have developed a dynamic extended folding strategy to predict RNA secondar

A comparison of the protective action of added egg yolks from five avian species to the cryopreservation of bull sperm

Cryopreservation of domestic animal sperm has been widely used for artificial insemination (AI), and egg yolk is one of the most commonly used cryoprotectants during the freezing-thawing process. The objectives of this study were to compare the effectiven

Avian influenza virus infection induces differential expression of genes in chicken kidney

The pathogenic process of highly pathogenic avian influenza virus (HPAIV) infection is poorly understood. To explore the differential expression of kidney genes as a result of HPAIV infection, two cDNA libraries were constructed from uninfected and infected kidneys by suppression subtractive hybridization (SSH). Fifteen genes including IFN-stimulated genes (ISG12), lymphocyte antigen 6 complex locus E gene (LY6E), matrix Gla protein gene (MGP), lysozyme gene, haemopoiesis related membrane protein I gene, KIAA1259, MGC68696, G6pe-prov protein gene (G6PC), MGC4504, alcohol dehydrogenase gene (ADH), glutathione S-transferase gene (GST), sodium-dependent high-affinity dicarboxylate transporter gene (SDCT), Synaptotagmin XV (SytXV) and two novel genes were found significantly up-regulated or dramatically suppressed. Differential expression of these genes was further identified by Northern blot. Functional analysis indicated that the regulation of their expression might contribute to the pathogenic process of HPAIV infection. In contrast, the increased expression of three IFN-stimulated genes named ISG12, LY6E, and haemopoiesis related membrane protein 1 gene might reflect host defense responses. Further study showed that ISG12 protein failed to directly interact with NS1 protein of HPAIV which expressed simultaneously in the organs where HPAIV replication occurred, by use of BacterioMatch two-hybrid system. Therefore, our findings may provide new insights into understanding the molecular mechanism underlying the pathophysiological process of HPAIV infection in chicken. (c) 2007 Elsevier Ltd. All rights reserved.

Detection of avian influenza virus subtype H5 using a biosensor based on imaging ellipsometry

A novel method is reported for the detection of avian influenza virus subtype H5 using a biosensor based on high spatial resolution imaging ellipsometry (IE). Monoclonal antibodies specific to H5 hemagglutinin protein were immobilized on silicon wafers and used to capture virus particles. Resultant changes on the surface of the wafers were visualized directly in gray-scale on an imaging ellipsometry image. This preliminary study has shown that the assay is rapid and specific for the identification of avian influenza virus subtype H5. Compared with lateral-flow immunoassays, this biosensor not only has better sensitivity, but can also simultaneously perform multiplexed tests. These results suggest that this biosensor might be a valuable diagnostic toot for avian influenza virus detection. (c) 2009 Elsevier B.V. All rights reserved.

Livestock grazing, plateau pikas and the conservation of avian biodiversity on the Tibetan plateau

On the Qinghai-Tibet plateau increased livestock numbers have resulted in degradation of the grasslands with potential impacts on native biodiversity. Concurrently, perceived increases in populations of native small mammals such as plateau pikas (Ochotona curzoniae) have led to poisoning programs, with uncertain impacts on species such as ground-nesting birds. We explored the relationships between the local seasonal abundance of small birds and (1) the density of pika burrows; (2) livestock grazing practices; and (3) local poisoning of pikas. Around Naqu prefecture, central Tibet, we used a nested experimental design to collect data from areas rested from grazing over summer, nearby areas with year-round grazing and areas subjected to pika poisoning. Additional data were collected from a site where grazing had not occurred for at least 4 years prior to the study. Poisoning pikas in spring had no detectable effect on the local abundance of birds the following autumn. However, two ground-nesting species, white-rumped and rufous-necked snowfinches, showed positive associations with the density of pika burrows, indicating that long-term 'pika poisoning could reduce the density of these species by reducing the density of pika burrows. Rufous-necked snowfinches and non ground-nesting species including horned larks and common hoopoes showed positive responses to reduced grazing pressure from livestock, particularly in the long-rested site, indicating current grazing levels could be having a negative impact on these species. Conservation of small passerine biodiversity in this system will require changed management practices for livestock and pikas that consider the complex three-way interaction between livestock grazing, pikas and small birds. (C) 2008 Elsevier Ltd. All rights reserved.

H5N1 avian influenza re-emergence of Lake Communication Qinghai: phylogenetic and antigenic analyses of the newly isolated viruses and roles of migratory birds in virus circulation

Highly pathogenic avian influenza H5N1 virus has swept west across the globe and caused serious debates on the roles of migratory birds in virus circulation since the first large-scale outbreak in migratory birds of Lake Qinghai, 2005. In May 2006, another outbreak struck Lake Qinghai and six novel strains were isolated. To elucidate these QH06 viruses, the six isolates were subjected to whole-genome sequencing. Phylogenetic analyses show that QH06 viruses are derived from the lineages of Lake Qinghai, 2005. Five of the six novel isolates are adjacent to the strain A/Cygnus olor/Croatia/1/05, and the last one is related to the strain A/duck/Novosibirsk/ 02/05, an isolate of the flyway. Antigenic analyses suggest that QH06 and QH05 viruses are similar to each other. These findings implicate that QH06 viruses of Lake Qinghai may travel back via migratory birds, though not ruling out the possibility of local circulation of viruses of Lake Qinghai.

核基因在鸟类分子系统发育学研究中的应用

核基因作为一种新的遗传标记,近年来被广泛应用于鸟类分子系统发育研究中.核基因与线粒体基因位于不同的遗传载体上,因此被引入到系统发育学研究中为物种树的重建提供独立的证据.常用的外显子标记为重组激活基因1(RAG-1),重组激活基因2(RAG-2),癌基因c-myc,原癌基因c-mos,它们由于缓慢的进化速率而被用于鸟类高级分类阶元的系统学研究中.常用的内含子标记是β纤维蛋白原基因内含子7(β-fibrinogen intron7,β-fibint7),肌红蛋白基因内含子Ⅱ(myoglobin intionⅡ).内含子标记通常与线粒体序列联合使用,形成具有互补系统发育信号的数据集,应用于各种分类阶元的系统学研究中.

云南鸟类目的新记录(鹱形目：鹱科：纯褐鹱)

国家自然科学基金资助项目(30270174)

近代鸟类分类与系统发育研究进展

简要综述了宏观和微观领域的鸟类分类学研究进展。宏观领域介绍了传统形态分类学、数值分类学和支序 分类学, 结合鸣声分析强调支序分类学的应用。微观领域介绍了Sibley 分类系统和近年来出现的主要基于mtDNA 的鸟类系统学研究。通过对大量研究工作的分析提出该领域今后应进行综合性研究。

Molecular systematics and historical biogeography of the Black-browed Barbet species complex (Megalaima oorti)

Although Southeast Asia is a global biodiversity hotspot, the tempo and mode of avian diversification there has not been well studied. We investigated the history of the diversification of an endemic Asian tropical bird, the Black-browed Barbet Megalaima

H5N2亚型禽流感病毒血凝素裂解位点碱性氨基酸对应mRNA核苷酸的二级结构分析

以H5N2亚型禽流感病毒毒株血凝素蛋白裂解位点碱性氨基酸为研究对象,对其密码子偏好性和对应mRNA序列的折叠二级结构特点进行研究和分析.旨在探讨裂解位点氨基酸对应mRNA核苷酸片段的二级结构与病毒致病力的关系,希望能对禽流感病毒的研究提供一些基础性信息.将mRNA样本按照序列等步长递增的方法,用RNAstructure 4.1程序预测这些样本的动态延伸折叠二级结构.序列和结构的分析结果:裂解位点的碱性氨基酸对富含腺嘌呤的密码子有强烈偏好;与碱性氨基酸对应的mRNA片段上的核苷酸主要位于折叠二级结构的单链环区,少数位于配对螺旋区.结果表明:裂解位点氨基酸对应的mRNA核苷酸形成发夹端环的大小与其碱性氨基酸的多少具有正相关性.