Altered actin cytoskeleton in ageing eggs of starfish affects fertilization process.

Altered actin cytoskeleton in ageing eggs of starfish affects fertilization process.
Exp Cell Res. 2019 May 10;:
Authors: Limatola N, Vasilev F, Chun JT, Santella L
Abstract
Integrity of oocytes is of pivotal interest in the medical and zootechnical practice of in vitro fertilization. With time, oocytes undergo deterioration in quality, and ageing oocytes often exhibit compromised competence in fertilization and the subsequent embryonic development. With ageing oocytes and eggs of starfish (Astropecten aranciacus), we addressed the issue by examining changes of the subcellular structure and their performance at fertilization. Ageing eggs were simulated in two different experimental paradigms: i) oocytes were overmatured by 6 h stimulation with 1-methyladenine (1-MA); ii) oocytes were removed from the gonad and maintained in seawater for 24 or 48 h before applying the hormonal stimulation (1-MA, 70 min). These eggs were compared with normally matured eggs (stimulated after isolation from the gonad with 1-MA for 70 min) with respect to the sperm-induced intracellular Ca2+ signaling and the structural changes of the egg surface. The cytoskeletal and ultrastructural differences in these eggs were assessed by confocal and transmission electron microscopy, respectively. In the two categories of ageing eggs, we have found remarkable structural modifications of the actin cytoskeleton and the cortical vesicles beneath the plasma membr...

Source: Experimental Cell Research - May 9, 2019 Category: Cytology Authors: Limatola N, Vasilev F, Chun JT, Santella L Tags: Exp Cell Res Source Type: research