How to get a metre of DNA into a tiny space while preserving its functional characteristics? This question seems easy to pose, but the answer is far from being trivial. Facing this riddle, salvation came from technical improvements in microscopy and in situ hybridisation techniques applied to cytogenetics. Here, we would like to look into the past at one of these pure cytogenetics articles that makes a breakthrough in addressing this question in plant science. Our choice fell on the work published two decades ago by Fransz et al. (2002). Besides the elegant manner in which DNA probes were organised to bring into light the out-looping arrangement of interphase chromosomes in Arabidopsis thaliana nuclei, this article perfectly illustrates that painting is not reserved to the fine art. As for whether emotional expression prioritised by artists can sometimes hide behind scientific empirical evidence, there is only a small step to make to the general case.

Mouse antral oocytes can be classified in two different types termed SN or NSN oocytes, depending on the presence or absence, respectively, of a ring of Hoechst 33342-positive chromatin surrounding the nucleolus. The aim of the present study was to test the developmental competence to blastocyst of the two types of oocytes. Here we show that following isolation, classification and culture of cumulus-free antral oocytes, 14.7% and 74.5% of NSN and SN oocytes, respectively, reached the metaphase II stage. When fertilised and further cultured none of the metaphase II NSN oocytes developed beyond the 2-cell stage whilst 47.4% of the metaphase II SN oocytes reached the 4-cell stage and 18.4% developed to blastocyst. The findings reported in this paper may contribute to improved procedures of female gamete selection for in vitro fertilisation of humans and farm animals. Furthermore, the selection of oocytes with better developmental potential may be of interest for studies on nuclear/cytoplasm interaction, particularly in nuclear-transfer experiments.