2017考博英语阅读题源经济学人文章每日精析（八十八）

　　The anatomy-related adaptations were those that seemed to control the development of the pandas’ second thumbs. Two genes in particular, DYNC2H1 and pericentrin, have mutations that cause identical changes in each type of panda in the proteins encoded by these genes. In mice, mutations in these genes are known to encourage extra digits to grow, so it is not unreasonable to suspect that they are also the cause of this in pandas.

　　与生物体结构相关的基因有可能控制熊猫第二拇指的生长。特别是DYNC2H1和中心粒周围蛋白这两种基因的突变，会导致在每种类型的熊猫中，由这两种基因控制编码的蛋白质产生相同变化。在小鼠中，这些基因的突变可导致小鼠额外足趾的生长，所以有理由认为熊猫第二拇指生长的原因也是基因突变。

　　pericentrin 中心粒周蛋白

　　The appetite-modifying change involved one of the disabled genes. When working, this gene encodes a protein which forms part of the tongue’s taste buds for umami, a savoury “meatiness” separate from the other four tastes of sweetness, sourness, bitterness and saltiness. Umami perception is stimulated byglutamic acid, one of the 20 amino acids that make up proteins—but one that is more characteristic of animal proteins than plant ones. Sensitivity to umami is valuable to a carnivore but unnecessary (and possibly harmful) to a herbivore.

　　食欲修饰基因的改变是丧失功能的基因中的一个。该基因在工作时，会编码一种组成舌头味蕾中鲜味的蛋白质，是区别于酸甜苦咸四种味道的可口的“肉味”。鲜味感觉是由谷氨酸激发的产生的，它是组成蛋白质的20个氨基酸之一，但相比于植物蛋白，它更具有动物蛋白的特性。对鲜味的敏感程度对食肉动物而言非常重要，但对食草动物来说，这是不必要并且可能是有害的。

　　umami [u'mɑmi] n.鲜味

　　stimulate ['stɪmjʊleɪt] v.刺激

　　glutamic acid 谷氨酸

　　amino acid [ə'miːnəʊ] [生化]氨基酸

　　herbivore ['hɜːbɪvɔː] n.食草动物

　　The other genetic convergences Dr Hu recorded were related to the digestion and metabolism of substances scarce in, or absent from, bamboo. He and his colleagues noted parallel changes in the genes for three digestive enzymes whose job is to liberate two particular amino acids, lysine and arginine, from proteins. Both lysine and arginine are abundant in meat, but in short supply in bamboo. The team also noted parallel changes in four genes that encode proteins involved in the metabolism of two vitamins, A and B12, and of arachidonic acid, a lipid essential for bodily function. All of these are scarce or non-existent in bamboo as well. Exactly how the genetic changes seen alter the effectiveness of the proteins involved remains to be determined. But the prediction would be that they enhance the availability of the nutrients in question.

　　胡博士记录的其他遗传转化与竹子中缺乏或缺失的物质的消化和代谢有关。他的团队发现三种消化酶基因相似的改变，这些消化酶的作用是从蛋白质中释放两种特殊的氨基酸，赖氨酸和精氨酸。肉类中富含赖氨酸和精氨酸，而在竹子中却很缺乏。该团队还注意到四种变化相同的基因，这些基因编码的蛋白质包括新陈代谢中所需的维生素A，维生素B12和机体功能必需的脂质-花生四烯酸。而这些在竹子中非常缺乏甚至不存在。基因变化具体是如何改变所涉及蛋白质的有效性仍有待确定。但可预测的是，它们增强了讨论中的营养素的可利用性。

　　arachidonic acid [ˈærəki'dɔnik] [ˈæsid] [有化]花生四烯酸

　　The upshot is that the two pandas do indeed seem to have similar genetics underlying their similar peculiarities. Such similarities are, admittedly, easier to find than different genetic routes to the same outcome would be. But Dr Hu has established that, at least in the case of pandas, natural selection has often taken the same paths to arrive at the same outcomes.

　　结论是：基于两类熊猫的相似特性，它们确实有相似基因。(期待您的翻译，明天会有针对这句话的长难句解析哟~)但是胡博士已经确定，至少在熊猫中，自然选择通常以相同的途径达到相同的结果。

　　Upshot ['ʌpʃɒt] 结果

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