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A New Type I Peritrophic Membrane Protein from Larval Holotrichia oblita (Coleoptera: Melolonthidae) Binds to Chitin

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      Peritrophic membranes (PMs) are composed of chitin and protein. Chitin and protein play important roles in the structural formation and function of the PM. A new type I PM protein, HoCBP76, was identified from the Holotrichia oblita. HoCBP76 was shown as a 62.3 kDa protein by SDS-PAGE analysis and appeard to be associated with the PM throughout its entire length. In H. oblita larvae, the midgut is the only tissue where HoCBP76 could be detected during the feeding period of the larvae. The predicted amino acid sequence indicates that it contains seven tandem chitin binding domains belonging to the peritrophin-A family. HoCBP76 has chitin binding activity and is strongly associated with the PM. The HoCBP76 was not a mucin-like glycoprotein, and the consensus of conserved cysteines appeared to be CX 13–17CX 5CX 9CX 12CX 7C. Western blot analysis showed that the abundance of HoCBP76 in the anterior, middle and posterior regions of the midgut was similar, indicating that HoCBP76 was secreted by the whole midgut epithelium, and confirmed the H. oblita PM belonged to the Type I PM. Immunolocalization analysis showed that HoCBP76 was mainly localized in the PM. The HoCBP76 is the first PM protein found in the H. oblita; however, its biochemical and physiological functions require further investigation.

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      Most cited references 33

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          Formed of proteins, glycoproteins, and chitin microfibrils in a proteoglycan matrix, the peritrophic matrix (PM) separates the food from the midgut epithelium in most but not all insects. A PM occurs in two forms. A type I PM is delaminated from the entire midgut epithelium and, in some cases, may only be formed in response to feeding and the type of meal ingested. A type II PM is produced by a specialized region of the anterior midgut called the cardia and forms a continuous sleeve (or sleeves) that is always present. As it is positioned between food and midgut epithelium, the PM plays key roles in the intestinal biology of the insect. The PM may protect the midgut epithelium from mechanical damage and insult from pathogens and toxins; it must act as a semipermeable membrane regulating passage of molecules between the different midgut compartments; and it may separate the midgut lumen into different, physiologically significant compartments.

            Author and article information

            [1 ]Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050035, Hebei, China; E-Mail: xiaominliu1981@
            [2 ]Plant Science and Technology College, Beijing University of Agriculture, Beijing 102206, China
            [3 ]College of Plant Protection, Agricultural University of Hebei/Biological Control Centre of Plant Pathogens and Plant Pests of Hebei Province, Baoding 071001, Hebei, China; E-Mails: liruijun@ (R.L.); zhaodan@ (D.Z.); yjihn@ (X.L.)
            [4 ]Shijiazhuang Development and Reform Commission, Shijiazhuang 050011, Hebei, China; E-Mail: lijie@
            Author notes

            Author Contributions

            Conceived and designed the experiments: WG. Performed the experiments: XML, JL, DZ, XNL. Analyzed the data: XML, RJL. Wrote the paper: XML, WG.

            [* ]Author to whom correspondence should be addressed; E-Mail: guowei@ ; Tel./Fax: +86-312-7528-178.
            Int J Mol Sci
            Int J Mol Sci
            International Journal of Molecular Sciences
            Molecular Diversity Preservation International (MDPI)
            April 2014
            22 April 2014
            : 15
            : 4
            : 6831-6842
            24758927 4013664 10.3390/ijms15046831 ijms-15-06831
            © 2014 by the authors; licensee MDPI, Basel, Switzerland

            This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (



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