Calderón-Fernández Gustavo M, Moriconi Débora E, Dulbecco Andrea B, Juárez M Patricia
Instituto de Investigaciones Bioquímicas de La Plata (CONICET-UNLP), Facultad de Ciencias Médicas, La Plata, Argentina.
J Med Entomol. 2017 Nov 7;54(6):1531-1542. doi: 10.1093/jme/tjx151.
The insect integument, formed by the cuticle and the underlying epidermis, is essential for insect fitness, regulation of lipid biosynthesis and storage, insect growth and feeding, together with development progress. Its participation in insecticide resistance has also been outlined. Triatoma infestans Klug (Hemiptera: Reduviidae) is one of the major vectors of Chagas disease in South America; however, genomic data are scarce. In this study, we performed a transcriptome analysis of the nymph integument in order to identify which genes are expressed and their putative role. Using the 454 GS-FLX sequencing platform, we obtained approximately 144,620 reads from the integument tissue. These reads were assembled into 6,495 isotigs and 8,504 singletons. Based on BLAST similarity searches, about 8,000 transcripts were annotated with known genes, conserved domains, and/or Gene Ontology terms.The most abundant transcripts corresponded to transcription factors and nucleic acid metabolism, membrane receptors, cell signaling, and proteins related to cytoskeleton, transport, and cell energy processes, among others. More than 10% of the transcripts-encoded proteins putatively involved in the metabolism of fatty acids and related components (fatty acid synthases, elongases, desaturases, fatty alcohol reductases), structural integument proteins, and the insecticide detoxification system (among them, cytochrome P450s, esterases, and glutathione transferases). Real-time qPCR assays were used to investigate their putative participation in the resistance mechanism. This preliminary study is the first transcriptome analysis of a triatomine integument, and together with prior biochemical information, will help further understandthe role of the integument in a wide array of mechanisms.
昆虫体壁由角质层和其下的表皮组成，对于昆虫的适应性、脂质生物合成与储存的调节、昆虫的生长与取食以及发育进程至关重要。其在昆虫抗药性方面的作用也已得到阐述。克鲁格锥蝽（半翅目：猎蝽科）是南美洲恰加斯病的主要传播媒介之一；然而，基因组数据却很匮乏。在本研究中，我们对若虫体壁进行了转录组分析，以确定哪些基因被表达及其假定作用。利用454 GS-FLX测序平台，我们从体壁组织中获得了约144,620条 reads。这些 reads 被组装成6,495个 isotigs 和8,504个单基因簇。基于BLAST相似性搜索，约8,000个转录本被注释了已知基因、保守结构域和/或基因本体术语。最丰富的转录本对应于转录因子和核酸代谢、膜受体、细胞信号传导以及与细胞骨架、运输和细胞能量过程相关的蛋白质等。超过10%的转录本编码的蛋白质可能参与脂肪酸及相关成分的代谢（脂肪酸合酶、延长酶、去饱和酶、脂肪醇还原酶）、体壁结构蛋白以及杀虫剂解毒系统（其中包括细胞色素P450、酯酶和谷胱甘肽转移酶）。实时定量PCR分析用于研究它们在抗性机制中的假定作用。这项初步研究是首次对锥蝽体壁进行转录组分析，结合先前的生化信息，将有助于进一步了解体壁在多种机制中的作用。
