密切的四足动物关系的长Latimeria通过血红蛋白序列表明
T Gorr1, T Kleinschmidt, H Fricke
1Max-Planck-Institut für Biochemie, Martinsried bei München, Germany.
Nature
|May 30, 1991
概括
龙 (Latimeria chalumnae) 是四足动物的最近亲属. 对其α-和β-环球蛋白链的分析显示,它与比其他鱼类更接近,支持其与陆地脊椎动物的进化联系.
科学领域:
- 进化生物学 进化生物学
- 分子遗传学分子遗传学
- 进行比较基因组学.
背景情况:
- 四足动物从水生祖先的进化起源仍然是进化生物学中的一个关键问题.
- 传统的分类已经提出灭绝的Rhipidistia,肺鱼 (Dipnoi) 或射线鱼 (Actinopterygii) 作为四足动物的最亲密的亲属.
- 鱼 (Latimeria chalumnae) 是一种活着的叶片鱼,它代表了理解四足动物祖先的关键血统.
研究的目的:
- 通过使用分子数据,研究龙相对于四足动物的遗传位置.
- 为了比较Latimeria的全球链序列与各种鱼类和两动物物种的全球链序列.
- 为了确定哪个活生生的鱼群表现出与四足动物最密切的分子关系.
主要方法:
- 确定大黄蜂血红蛋白的α-和β-环球蛋白链序列.
- 来自Latimeria,骨鱼,软骨鱼,鱼和成年两动物的全球蛋白链的比较序列分析.
- 识别同型序列匹配,以评估进化相关性.
主要成果:
- 洋的全球蛋白链与子血球蛋白的相似程度高于其他鱼类群体的血球蛋白.
- 拉蒂梅利亚的β-环球蛋白链与的β链相匹配54%,超过任何其他鱼类的匹配.
- 考虑到协同形态匹配,拉蒂梅里亚球蛋白链与子阶段的相同性比任何骨鱼都更大.
- 远的α链与类两动物的相似性比肺鱼的α链更高.
结论:
- 巨血红蛋白的主要结构提供了强有力的证据,证明它是四足动物的最近亲属.
- 分子数据,特别是全球链分析,完善了我们对鱼-四足动物过渡的理解.
- 这项研究支持将Actinistia (鱼) 作为四足动物的姐妹群体放在现存鱼类中.
相关概念视频
Fixed Action Patterns
A fixed action pattern (FAP) is a specific, hard-wired sequence of behaviors that occurs in response to an external stimulus, called a sign stimulus. The behavior is “fixed” because it is essentially unchangeable—proceeding similarly across individuals of a species every time it occurs.
Parental Care
Many animals exhibit parental care behavior, including feeding, grooming, and protecting young offspring. Parental care is universal in mammals and birds, which often have young that are born relatively helpless. Several species of insects and fish, as well as some amphibians, also care for their young.
Symbiosis
Symbiotic relationships are long-term, close interactions between individuals of different species that affect the distribution and abundance of those species. When a relationship is beneficial to both species, this is called mutualism. When the relationship is beneficial to one species but neither beneficial nor harmful to the other species, this is called commensalism. When one organism is harmed to benefit another, the relationship is known as parasitism. These types of relationships often...
Phylogeny
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire...
Predator-Prey Interactions
Predators consume prey for energy. Predators that acquire prey and prey that avoid predation both increase their chances of survival and reproduction (i.e., fitness). Routine predator-prey interactions elicit mutual adaptations that improve predator offenses, such as claws, teeth, and speed, as well as prey defenses, including crypsis, aposematism, and mimicry. Thus, predator-prey interactions resemble an evolutionary arms race.Although predation is commonly associated with carnivory, for...
Epiphytes, Parasites, and Carnivores
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the biosynthesis of the...


