Sequential oogenesis is controlled by an oviduct factor in the locusts Locusta migratoria and Schistocerca gregaria: Overcoming the doctrine that patency in follicle cells is induced by juvenile hormone. (July 2016)

• Record Type: Journal Article
• Authors: Seidelmann, Karsten; Helbing, Cornelia; Göbeler, Norman; Weinert, Heike
• Is Part Of: Journal of insect physiology. Volume 90(2016:Jul.)
• Page Start: 1
• Page End: 7
• Publication Date: 2016-07
• Subjects: Hormonal control -- Reproduction -- Vitellogenesis: yolk uptake -- Follicle cells -- Orthoptera: Acrididae; Insects -- Physiology -- Periodicals; Insectes -- Physiologie -- Périodiques; Insects -- Physiology; Periodicals; 571.157
• DOI: 10.1016/j.jinsphys.2016.03.008
• Languages: English
• ISSNs: 0022-1910

Abstract

Graphical abstract: Highlights: At sequential oogenesis, maturation is restricted to basal oocytes. Yolk-uptake is controlled by formation of spaces between follicle cells (patency). Patency of the follicle cell layer is induced by an oviduct factor (PIF). PIF originates from the oviductus lateralis and takes effect via the pedicel. Juvenile hormone is not able to induce patency, but amplifies the effect of PIF. Abstract: In insects that lay eggs in large clutches, yolk accumulation in each of the many ovarioles is restricted to the basal (terminal) oocyte, the one closest to the lateral oviduct. All succeeding (subterminal) oocytes remain small until the terminal oocytes finished their development and were ovulated into the oviduct. The major step regulating yolk uptake by terminal oocytes is the formation of gaps between cells of the follicle layer, a process termed patency. In the migratory as well as in the desert locust, patency is induced by a Patency Inducing Factor (PIF) produced by the lateral oviducts. PIF is secreted in all regions of the lateral oviducts and interacts with the basal follicle cells via the pedicel, a fine duct that connects an ovariole with the oviduct. By this mechanism, patency is triggered in the follicle cells of the terminal oocyte only, restricting yolk accumulation to the oocytes next to ovulation. In contrast to the previous hypothesis, juvenile hormone (JH) is not necessary to induce patency, rather JH amplifies the effect of PIF.