Evidence for a transcellular route for vitellogenin transport in the telotrophic ovary of Podisus nigrispinus (Hemiptera: Pentatomidae)

• Published in: Scientific reports Vol. 9; no. 1; pp. 16441 - 8
• Main Authors: Assis, Mírian Quintão, Dohanik, Virgínia Teles, Oliveira, Leandro Licursi de, Zanuncio, José Cola, Serrão, José Eduardo
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 11.11.2019; Nature Publishing Group UK
• Subjects: Animals; Cytoplasm; Endocytosis; Epithelium; Fat body; Female; Fluorescent Antibody Technique; Hemiptera; Hemiptera - physiology; Hemolymph; Immunofluorescence; Oocytes; Oocytes - metabolism; Oocytes - ultrastructure; Ovary - metabolism; Ovary - ultrastructure; Plasma; Podisus nigrispinus; Protein Transport; Vitellogenin; Vitellogenins - metabolism; Yolk
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-52789-z

Vitellogenin is the main yolk precursor protein in insect oocytes. It is synthesized in the fat body and released into the hemolymph. To reach the oocyte surface, vitellogenin must cross a single layer of follicular epithelium cells. The transport of vitellogenin across the follicular epithelium has been suggested to occur through the enlarged intercellular spaces (patency) by a paracellular route or by endocytosis by follicular cells and release onto oocyte surface in a transcelluar route. In this study, we investigated whether vitellogenin transport in the meroistic telotrophic ovary of Podisus nigrispinus (Hemiptera) occurs via a paracellular or transcellular route. Light and transmission electron microscopies showed that short cell-cell contacts with well-developed occluding septate junctions were present in follicular cells with patency. Immunofluorescence microscopy revealed the presence of vitellogenin receptors in the plasma membrane and of vitellogenin in the cytoplasm of follicular cells. Data suggest that cell-cell contacts serve as a barrier to large vitellogenin molecules and that this protein is transported via a transcellular route of receptor-mediated endocytosis.