Amore V, Belardinelli M, Guerra L, Buonocore F, Fausto A M, Ubero-Pascal N, Fochetti R
Dipartimento di Scienze Ambientali, Università della Tuscia, Viterbo, Italy.
Insect Mol Biol. 2009 Apr;18(2):203-11. doi: 10.1111/j.1365-2583.2008.00859.x.
Contrary to what was assumed regarding the presence of respiratory proteins in insects, a functional hemocyanin was recently found in larvae and adults of the stoneflies species Perla marginata, whereas in the close species Perla grandis, hemocyanin functionality was deduced from sequence data. In order to verify if the presence of this ancient trait is widespread within the order and to investigate why stoneflies have maintained it, we have extended the search for hemocyanin to species of other Plecoptera families. In particular, we assessed the presence of hemocyanin in the larval stage of nine Plecoptera species, belonging to six of the seven families of the European stonefly-fauna, and analyzed its potential functionality as deduced by sequence data. We cloned and sequenced the corresponding cDNAs and studied their expression with RT-PCR technique. Moreover, we performed homology studies using the deduced amino acid sequences. On the basis of our analysis, we hypothesized a functional role of the hemocyanin only for two species: Dinocras cephalotes and Isoperla grammatica (Perloidea). In all the investigated Nemouroidea and in Siphonoperla torrentium (Perloidea), this protein may have been lost. Larval size, life-cycle length, trophic role and environmental induction are discussed as possible explanations of these different physiological requirements.
与之前关于昆虫体内呼吸蛋白存在情况的假设相反，最近在石蝇物种缘斑佩尔石蝇的幼虫和成虫中发现了一种功能性血蓝蛋白，而在近缘物种大佩尔石蝇中，血蓝蛋白的功能是从序列数据推断出来的。为了验证这一古老特征在该目昆虫中是否广泛存在，并探究石蝇保留它的原因，我们将血蓝蛋白的搜索范围扩大到了其他襀翅目科的物种。特别是，我们评估了属于欧洲石蝇动物群七个科中六个科的九种襀翅目物种幼虫阶段血蓝蛋白的存在情况，并分析了序列数据推断出的其潜在功能。我们克隆并测序了相应的cDNA，并使用逆转录聚合酶链反应（RT-PCR）技术研究了它们的表达。此外，我们利用推导的氨基酸序列进行了同源性研究。根据我们的分析，我们推测血蓝蛋白仅对两种物种具有功能作用：头突异痣蟌和细纹等痣蟌（等痣蟌总科）。在所有被研究的叉襀总科物种以及急流管襀（等痣蟌总科）中，这种蛋白质可能已经丢失。幼虫大小、生命周期长度、营养作用和环境诱导被讨论为这些不同生理需求的可能解释。
