Comparative Proteomics and Expression Analysis of Five Genes in Epicauta chinensis Larvae from the First to Fifth Instar

Abstract

Blister beetle is an important insect model for both medicinal and pure research. Previous research has mainly focused on its biology and biochemistry, but very little data is yet available in the molecular biology. This study uses differential proteomics technology to analyze the soluble proteins extracted from each of the 5 instars larvae of Epicauta chinensis. 42 of the differentially-expressed proteins were identified successfully by MALDI-TOF/TOF-MS. Some of these proteins’ function and their expression profiles are analyzed. Our analysis revealed dynamics regulation of the following proteins: Axin-like protein pry-1 (APR-1), dihydrolipoyl dehydrogenase (DLD), vitellogenin (Vg) and lysozyme C (Lmz-S). APR-1 negatively regulates the Wnt signaling pathway. Its overexpression could result in embryo, leg, eye and ovary ectopica or malformation. DLD catalyzes the pyruvate into acetyl-CoA, the latter is the starting material of juvenile hormone (JH) and ipsdienol biosynthesis through the MVA pathway in insects. While Vg synthesis can be regulated by JH and stimulated by food factors. So DLD may affect the synthesis of JH, ipsdienol and Vg indirectly. The activity of lysozyme is an indicator of the immunity. Nutrition/food should be taken into account for its potential role during the development of larva in the future. Among the five genes and their corresponding proteins’ expression, only hsc70 gene showed a good correspondence with the protein level. This reflects the fluctuating relationship between mRNA and protein levels.

Comparative proteomic analysis between fifth‐instar nymphs and adults of Asian citrus psyllid Diaphorina citri

“…Additionally, two isoforms are detected only in adults. By contrast to the results with D. citri, the expression of enolase is highest in the fourth instar of the blister beetle Epicauta chinensis (Li et al, 2014).…”

“…Similarly, protein spots identified as heat shock protein in the present study are clearly up-regulated in adults over the nymphal stage. Similarly, the heat shock protein, Hsc70 is down-regulated in the fourth and fifth larval instars of E. chinensis compared with adults (Li et al, 2014). Heat shock proteins are particularly important for the transformation and thermotolerance of Strongyloides venezuelensis (Tsuji et al, 1996).…”

“…In several insect studies, proteomics has emerged as a powerful method for gaining insight into many physiological changes at the cellular level (Nyström, 2005;Seehuus et al, 2006;Zheng et al, 2011). The technique is reported to have successfully been used with many insects, particularly silkworm, mosquito, honeybee, fruit fly and cotton bollworm (Li et al, 2014). Most studies focus on insect immunity (Shi & Paskewitz, 2006), immunity-related proteins (e.g.…”

Optimization Method for Proteomic Analysis of the Larva and Adult Tissues of Plutella xylostella (L.) (Lepidoptera: Plutellidae)

“…Proteins were extracted according to the method described by Li et al (2014b) with slightly modification. Frozen tissues were added to 1 mL of phosphate buffer solution (PBS) (32.5 mM K 2 HPO 4 , 2.6 mM KH 2 PO 4 , 400 mM NaCl and protease inhibitor cocktail and placed on ice for 15 min.…”

“…The aim of the present study was to find an optimal method for extracting the total protein of P. xylostella for subsequent one-dimensional electrophoresis (1-DE) and 2-DE analyses. We employed five different extraction methods (Cilia et al 2009;Dong et al 2013;Li et al 2014b;Xie et al 2011;Zhang et al 2013) on both larva and adults of P. xylostella. These methods were chosen based on their successful used previously for extracting proteins from various insect samples including P. xylostella, albeit from different types of tissues or stages.…”