The oocyte is the only cell that can reprogram a somatic nucleus to totipotency. The process of reprogramming is, however, only partially understood, and is accompanied by both epigenetic and structural changes in the somatic nucleus. The oocyte components that are necessary for a successful reprogramming and remodeling are unknown. In this issue, Fulka H et al. demonstrate that rather than the insoluble nuclear envelope, together with chromatin-bound factors, or the cytoplasm alone, it is the soluble nuclear fraction that has a major effect upon the somatic nucleus (Fulka H, et al.: Dissecting the role of the germinal vesicle nuclear envelope and soluble content in the process of somatic cell remodeling and reprogramming. pp. 433-441). This fraction is essential for altering the size of the somatic nucleus as well as transcriptional silencing and efficient histone H3.3 incorporation.