AUGMENTATION AND DISPERSION OF IN VIVO MITOTIC APPARATUS OF LIVING MARINE EGGS

The effects of a number of organic reagents on the structure of the mitotic apparatus (MA) of several invertebrate eggs were investigated. In general, the agents induced either a large increase in the volume and retardation of the MA (hexylene glycol, dimethylsulfoxide, etc.) or caused it to partially or completely disappear (formamide, dithiodiglycol, dimethylacetamide, etc.). The immediate effects of the agents on the MA were reversible, but reversibility of embryonic development was only obtained if the eggs did not remain in the reagent for too long a time. The analysis of the specific effects of these agents suggests that the eggs utilized possess a pool of unoriented (or unpolymerized) MA material which may be reversibly affected by the agents studied. In the case of augmenting agents, the material is oriented into the MA or into aster-like bodies, in the case of dispersing agents, the material returns to the pool. Although no decision could be made as to whether the agents act directly or indirectly on the MA, the totality of the observations support the latter possibility. © 1969 Springer-Verlag.