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

Adaptive evolution of energy metabolism genes and the origin of flight in bats

Bat flight poses intriguing questions about how flight independently developed in mammals. Flight is among the most energy-consuming activities. Thus, we deduced that changes in energy metabolism must be a primary factor in the origin of flight in bats. The respiratory chain of the mitochondrial produces 95% of the adenosine triphosphate (ATP) needed for locomotion. Because the respiratory chain has a dual genetic foundation, with genes encoded by both the mitochondrial and nuclear genomes, we examined both genomes to gain insights into the evolution of flight within mammals. Evidence for positive selection was detected in 23.08% of the mitochondrial-encoded and 4.90% of nuclear-encoded oxidative phosphorylation (OXPHOS) genes, but in only 2.25% of the nuclear-encoded nonrespiratory genes that function in mitochondria or 1.005% of other nuclear genes in bats. To address the caveat that the two available bat genomes are of only draft quality, we resequenced 77 OXPHOS genes from four species of bats. The analysis of the resequenced gene data are in agreement with our conclusion that a significantly higher proportion of genes involved in energy metabolism, compared with background genes, show evidence of adaptive evolution specific on the common ancestral bat lineage. Both mitochondrial and nuclear-encoded OXPHOS genes display evidence of adaptive evolution along the common ancestral branch of bats, supporting our hypothesis that genes involved in energy metabolism were targets of natural selection and allowed adaptation to the huge change in energy demand that were required during the origin of flight.

天然来源具有抗HIV 活性的多肽和蛋白类化合物

　从天然药物中寻找高效低毒的抗HIV/ AIDS 活性化合物和先导化合物是国内外新药研制中非 常活跃的领域之一,也应该是我国近期创制新药的一条捷径。来源于动植物、海洋生物、微生物以及人体等中 的许多天然化合物具有抗HIV 活性。本文仅对天然来源的多肽和蛋白类化合物抗HIV 的研究简要综述。

云南省两栖动物一新纪录——阔褶蛙

下载PDF阅读器2008年3月13日,在云南省勐仑中国科学院西双版纳热带植物园(21°4′N,101°25′E,570 m)采集到一种蛙类标本,经鉴定为阔褶蛙Rana latouchii,为云南省新纪录.标本保存于西华师范大学生命科学学院标本室.简报如下

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独龙江为伊洛瓦底江流域的上游,地处云南省的西北部,位于北纬27°40'-28°45',东经97°45'-98°23'之间,整个流域呈弯曲的狭长条状镶嵌在喜马拉雅弧形构造的大拐弯部位.干流总长211.3 km,流域总面积4 327 km2.它北连深厚高耸的青藏高原,东接巍峨峻秀的高黎贡山,西界南北逶迤的担当力卡山与缅甸印度毗邻.

烟田烟蚜茧蜂的活动规律及其对烟蚜的防治效果

田间释放烟蚜茧蜂能很好地抑制烟蚜种群数量的增长。以常规施药烟田、不施药烟田作对照 ,在前期其对烟蚜的相对防效分别为 8.4%和 5 2 .8% ,中期为 6 4.0 %～ 79.0 %和 6 8.6 %～ 82 .3% ,后期为 93.0 %和 93.5 %。放蜂田烟蚜茧蜂成虫喜欢在烟株中下部叶片活动 ,1 3∶0 0～ 1 4∶0 0是其在烟株中下部活动的高峰期。烟蚜茧蜂对烟株下部叶片上烟蚜的较强选择性与烟蚜密度无关 ,下部叶片上的僵蚜数量均显著高于中、上和顶部。 1 3∶0 0～ 1 4∶0 0利用生物农药对烟株上部叶片上的烟蚜进行防治 ,既是烟蚜茧蜂与生物农药集成组装的切合点 ,又是保护利用田间烟蚜茧蜂的有效措施。

内含子序列“三碱基组”的信息分析

在对编码序列的碱基分布作大量统计分析的基础上，对内含子序列中Ｇ、Ｃ的分布作了统计分析．发现内含子在“三碱基组”的意义下，第一位上（Ｇ＋Ｃ）含量占优势．如果将同一基因的外显子三联密码和内含子“三碱基组”做比较，发现在内含子中出现而外显子中没有的那些三碱基组，它们大多属于Ｌｉó所列出的“非偏爱”密码

菊小长管蚜的化学防治研究

菊小长管蚜Macrosiphorniella sanborni是昆明地区花卉主要害虫之一，该虫对菊花嫩叶，嫩梢，花柄及花勒为害率达65.0%，个别大棚高达100，损失产量25.0%。室内外用1.8爱福丁3000，2500，2000倍液敌敌畏1500，1000，800倍液进行毒杀试验，爱福丁室内的毒杀率达96.6%，敌敌畏达96.3%；田间爱福丁害83.39%，敌敌畏达80.20%。