title: Disruption of the salivary gland muscle in tsetse, Glossina pallidipes Austen, as a result of salivary gland hypertrophy virus infection.
abstract: The secretory region of the salivary glands in Glossina pallidipes Austen (Diptera: Glossinidae) is characterized by an external muscle layer. Scanning electron microscopy and transmission electron microscopy investigations provide a detailed description of the longitudinal muscle fibres and a comparison of their structure when affected by salivary gland hypertrophy virus. The virus is responsible for hypertrophy of the salivary glands in symptomatic flies, specifically of the muscle fibres, the cytoarchitecture of which is completely altered. Although observations did not reveal viral particles in the muscle cells of either asymptomatic or symptomatic flies, muscle fibres were enlarged and detached from one another and their associated basement membrane only in symptomatic flies. A decrease in type IV collagen labelling in the basement membrane of the muscles in symptomatic flies is reported and is considered a potential cause of the salivary gland muscle alteration and, possibly, myopathy. The maintenance of an organized muscular layer is essential for the normal secretion of saliva and hence its pathology in symptomatic tsetse flies could affect the normal transmission of the trypanosome that develops inside the salivary gland epithelium. Therefore, a better understanding of the possible role of the virus is essential in order to elucidate its impact on salivary deployment in symptomatic flies.
authors.affiliation: Dipartimento per la Innovazione nei Sistemi Biologici, Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Guerra
authors.affiliation: Department of Plant, Soil and Insect Sciences, Division of Entomology, Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA, U.S.A.
authors.forename: J G
authors.initials: JG
authors.lastname: Stoffolano
authors.affiliation: Dipartimento per la Innovazione nei Sistemi Biologici, Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy.
authors.forename: M C
authors.initials: MC
authors.lastname: Belardinelli
authors.affiliation: Centro Grandi Attrezzature (CGA), Sezione di Microscopia Elettronica Università degli Studi della Tuscia, Viterbo, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Gambellini
authors.affiliation: Centro Grandi Attrezzature (CGA), Sezione di Microscopia Elettronica Università degli Studi della Tuscia, Viterbo, Italy.
authors.forename: A R
authors.initials: AR
authors.lastname: Taddei
authors.affiliation: Dipartimento per la Innovazione nei Sistemi Biologici, Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy.
authors.forename: V Laghezza
authors.initials: VL
authors.lastname: Masci
authors.affiliation: Dipartimento per la Innovazione nei Sistemi Biologici, Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Fausto
mesh_terms: D000818:Animals; D004267:DNA Viruses / Q000502:physiology*; D005260:Female; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D012469:Salivary Glands / Q000033:anatomy & histology / Q000254:growth & development / Q000648:ultrastructure / Q000821:virology; D014370:Tsetse Flies / Q000033:anatomy & histology / Q000254:growth & development* / Q000648:ultrastructure / Q000821:virology*
keywords: Basement membrane; GpSGHV; metalloproteases; muscle fibres; myopathy; type IV collagen