title: Interaction between SWP9 and Polar Tube Proteins of the Microsporidian Nosema bombycis and Function of SWP9 as a Scaffolding Protein Contribute to Polar Tube Tethering to the Spore Wall.
abstract: All microsporidia possess a unique, highly specialized invasion mechanism that involves the polar tube and spore wall. The interaction between spore wall proteins (SWPs) and polar tube proteins (PTPs) in the formation, arrangement, orderly orientation, and function of the polar tube and spore wall remains to be determined. This study was undertaken to examine the protein interactions ofNosema bombycisSWP7 (NbSWP7), NbSWP9, and PTPs. Coimmunoprecipitation, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and yeast two-hybrid data demonstrated that NbSWP9, but not NbSWP7, interacts with NbPTP1 and NbPTP2. Furthermore, immunoelectron microscopy (IEM) showed that NbSWP9 was localized mainly in the developing polar tube of sporoblasts, while NbSWP7 was found randomly in the cytoplasm. However, both NbSWP9 and NbSWP7 were located in the polar tube and spore wall ofN. bombycismature spores. The reason why NbSWP7 was localized to the polar tube may be due to the interaction between NbSWP9 and NbSWP7. Interestingly, the majority of NbSWP9, but not NbSWP7, accumulated in the beginning part of the extruded polar tube and the ruptured spore wall called the anchoring disk (AD) when the mature spores germinated under weak-alkaline environmental stimulation. Additionally, anti-NbSWP9 antibody reduced spore germination in a dose-dependent manner. In conclusion, our study further confirmed that NbSWP9 is a scaffolding protein that not only anchors and holds the polar tube but also tethers the polar tube to the spore wall.
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|International Academy of Targeted Therapeutics and Innovation, Chongqing Key Laboratory of Kinase Modulators as Innovative Medicine, Chongqing Engineering Laboratory of Targeted and Innovative Therapeutics, Chongqing University of Arts and Sciences, Chongqing, People's Republic of China.|College of Forestry and Life Sciences, Chongqing University of Arts and Sciences, Chongqing, People's Republic of China.
authors.forename: Donglin
authors.initials: D
authors.lastname: Yang
authors.affiliation: Foreign Language Department, Chongqing Water Resources and Electric Engineering College, Chongqing, People's Republic of China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Pai
authors.initials: P
authors.lastname: Peng
authors.affiliation: College of Life Sciences, Chongqing Normal University, Chongqing, People's Republic of China.
authors.forename: Xiaoqun
authors.initials: X
authors.lastname: Dang
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Tian
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Mengxian
authors.initials: M
authors.lastname: Long
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Yujiao
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Huihui
authors.initials: H
authors.lastname: Du
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Song
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|College of Forestry and Life Sciences, Chongqing University of Arts and Sciences, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China.|College of Life Sciences, Chongqing Normal University, Chongqing, People's Republic of China.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Zeyang
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, People's Republic of China gqpan@swu.edu.cn.|Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing, People's Republic of China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Pan
mesh_terms: D002473:Cell Wall / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism*; D016818:Nosema / Q000502:physiology* / Q000648:ultrastructure; D011485:Protein Binding; D013172:Spores, Fungal
chemical_list: D005656:Fungal Proteins
keywords: germination; interaction; microsporidia; polar tube protein; spore wall protein