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Molecular characterization of digestive proteinases and sequence analysis of midgut cDNA transcripts of the yellow mealworm, Tenebrio molitor L. Insect Mol Biol

Department of Entomology, Kansas State University, Manhattan, KS, USA.
Insect Molecular Biology (Impact Factor: 2.98). 09/2007; 16(4):455-68. DOI: 10.1111/j.1365-2583.2007.00740.x
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ABSTRACT Peptidase sequences were analysed in randomly picked clones from cDNA libraries of the anterior or posterior midgut or whole larvae of the yellow mealworm, Tenebrio molitor Linnaeus. Of a total of 1528 sequences, 92 encoded potential peptidases, from which 50 full-length cDNA sequences were obtained, including serine and cysteine proteinases and metallopeptidases. Serine proteinase transcripts were predominant in the posterior midgut, whereas transcripts encoding cysteine and metallopeptidases were mainly found in the anterior midgut. Alignments with other proteinases indicated that 40% of the serine proteinase sequences were serine proteinase homologues, and the remaining ones were identified as either trypsin, chymotrypsin or other serine proteinases. Cysteine proteinase sequences included cathepsin B- and L-like proteinases, and metallopeptidase transcripts were similar to carboxypeptidase A. Northern blot analysis of representative sequences demonstrated the differential expression profile of selected transcripts across five developmental stages of Te. molitor. These sequences provide insights into peptidases in coleopteran insects as a basis to study the response of coleopteran larvae to external stimuli and to evaluate regulatory features of the response.

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    Insect Molecular Biology and Ecology, Edited by Klaus H. Hoffmann, 11/2014: pages 395; CRC press.
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    • "The occurrence of multiple isoforms may provide adaptive advantages for insects feeding on plants containing inhibitors. Therefore, it is not surprising that during the past decades, a large number of protease encoding genes were identified to be present in the digestive system of many different insects (Bown et al., 1997; Gatehouse et al., 1997; Ge et al., 2012; Marshall et al., 2008; Oliveira-Neto et al., 2004; Pedra et al., 2003; Prabhakar et al., 2007; Simpson et al., 2007). "
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