Novel technique for definite blastomere inhibition and distribution of maternal RNA in sterlet Acipenser ruthenus embryo

The cleavage pattern of a vertebrate's embryo is either holoblastic (complete) or meroblastic (partial). Sturgeon and other basal bony fishes represent a transition of the cleavage pattern. To understand the transition, it is essential to develop an effective technique for the inhibition of specific blastomere cleavage. So far, various studies have demonstrated that diatom-derived polyunsaturated aldehyde (PUA), 2,4-decadienal (DD)-a model aldehyde for experimental studies-adversely affects the developing embryos of several aquatic species. In this study, we employed DD for inhibition of cleavage of a definite blastomere in sturgeon embryos under various conditions. The effective treatment was found to be a combination of DD injection (0.01 v/v) and visible light (44.86-91.15 W m(-2)). Notably, DD injection or light irradiation alone cannot inhibit cleavage. Furthermore, spatial RNA localization analysis using quantitative polymerase chain reaction (qPCR)-tomography revealed that the localized pattern of selected maternal messenger ribonucleic acids (mRNAs) remained constant along the animal-vegetal (A-V) axis, which suggests that RNA localization is completed by the end of oogenesis and that early embryonic cleavage is not required for A-V asymmetry preservation.

Automated summary

The cleavage pattern of vertebrate embryos can be holoblastic or meroblastic, with sturgeon representing a transition in this pattern. Studies have shown that using a specific compound can inhibit embryo cleavage, and early embryonic cleavage may not be necessary for maintaining animal-vegetal axis symmetry.