Structural Variations and 3D Structure of the Populus Genus

Populus is one of the most important genera of Salicaceae and consists of various species. During the evolutionary process, the Populus species maintain a relatively stable karyotype, but there are also certain structural variations, which have a significant impact on genotype specification and environmental adaptabilities, such as the repeated turnovers of the ‘XY/ZW’ sex-determination system, gene copy number variations, and different tolerance to adversity. Furthermore, the different three-dimensional genome structures among Populus species caused by structural variations revealed low conservation of 3D genomes, including chromatin interactions, ‘A/B’ compartment switching, and TAD distribution. This chapter briefly summarized the genomic structural variations of Populus species, and their impacts on sex-determination system turnovers and three-dimensional genome differences, providing theoretical support for further research.