Hi-M: a multiplexed microscopy technology to simultaneous visualize genome organization and transcription in the developing Drosophila embryo

CARDOZO GIZZI, ANDRES M.; CATTONI, DIEGO I.; FICHE, JEAN-BERNARD; ESPINOLA, SERGIO M.; CAVALLI, GIACOMO; LAGHA, MOUNIA; NOLLMANN, MARCELO

Buenos Aires

Congreso; Latin American Society for Developmental Biology Meeting 2019; 2019

Latin American Society for Developmental Biology

Eukaryotic chromosomes are organized in multiple scales, from nucleosomes to chromosome territories. Recently, genome-wide methods identified an intermediate level of chromosome organization, topologically associating domains (TADs), that play key roles in transcriptional regulation. However, these methods cannot directly examine the interplay between transcriptional activation and chromosome architecture while maintaining spatial information. Here, we present a multiplexed, sequential imaging approach (Hi-M) that permits the simultaneous detection of chromosome organization and transcription in single nuclei. This allowed us to unveil the changes in 3D chromatin organization occurring upon transcriptional activation and homologous chromosome un-pairing during the awakening of the zygotic genome in intact Drosophila embryos. Excitingly, the ability of Hi-M to explore the multi-scale chromosome architecture with spatial resolution at different stages of development or during the cell cycle will be key to understand the mechanisms and consequences of the temporal and spatial organization of the genome.