title: Characterization of a novel spore wall protein NbSWP16 with proline-rich tandem repeats from Nosema bombycis (microsporidia).
abstract: Nosema bombycis, a pathogen of silkworm pebrine, is an obligate unicellular eukaryotic parasite. It is reported that the spore wall proteins have essential functions in the adherence and infection process of microsporidia. To date, the information related to spore wall proteins from microsporidia is still limited. Here, a 44 kDa spore wall protein NbSWP16 was characterized in N. bombycis. In NbSWP16, a 25 amino acids signal peptide and 3 heparin binding motifs were predicted. Interestingly, a region that contains 3 proline-rich tandem repeats lacking homology to any known protein was also present in this protein. The immunofluorescence analysis (IFA) demonstrated that distinct fluorescent signals were detected both on the surface of mature spores and the germinated spore coats. Immunolocation by electron microscopy revealed that NbSWP16 localized on the exospore regions. Finally, spore adherence analysis indicated that spore adherence to host cell was decreased more than 20% by anti-NbSWP16 blocking compared with the negative control in vitro. In contrast with anti-NbSWP16, no remarkable decrement inhibition was detected when antibodies of NbSWP16 and NbSWP5 were used simultaneously. Collectively, these results suggest that NbSWP16 is a new exospore protein and probably be involved in spore adherence of N. bombycis.
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Xiaoqun
authors.initials: X
authors.lastname: Dang
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Fangyan
authors.initials: F
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Tian
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silkworm genome Biology,Southwest University,Chongqing 400716,China.
authors.forename: Zeyang
authors.initials: Z
authors.lastname: Zhou
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D012831:Bombyx / Q000469:parasitology; D002448:Cell Adhesion; D019084:Fluorescent Antibody Technique, Indirect; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D006790:Host-Parasite Interactions; D016253:Microscopy, Immunoelectron; D016818:Nosema / Q000737:chemistry* / Q000235:genetics; D021382:Protein Sorting Signals / Q000235:genetics; D016415:Sequence Alignment; D013172:Spores, Fungal / Q000737:chemistry / Q000235:genetics; D020080:Tandem Repeat Sequences / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D021382:Protein Sorting Signals
keywords: Nosema bombycis