Chromatin topology reorganization and transcription repression by PML-RARα in acute promyeloid leukemia

oleh: Ping Wang, Zhonghui Tang, Byoungkoo Lee, Jacqueline Jufen Zhu, Liuyang Cai, Przemyslaw Szalaj, Simon Zhongyuan Tian, Meizhen Zheng, Dariusz Plewczynski, Xiaoan Ruan, Edison T. Liu, Chia-Lin Wei, Yijun Ruan

Format: Article
Diterbitkan: BMC 2020-05-01

Deskripsi

Abstract Background Acute promyeloid leukemia (APL) is characterized by the oncogenic fusion protein PML-RARα, a major etiological agent in APL. However, the molecular mechanisms underlying the role of PML-RARα in leukemogenesis remain largely unknown. Results Using an inducible system, we comprehensively analyze the 3D genome organization in myeloid cells and its reorganization after PML-RARα induction and perform additional analyses in patient-derived APL cells with native PML-RARα. We discover that PML-RARα mediates extensive chromatin interactions genome-wide. Globally, it redefines the chromatin topology of the myeloid genome toward a more condensed configuration in APL cells; locally, it intrudes RNAPII-associated interaction domains, interrupts myeloid-specific transcription factors binding at enhancers and super-enhancers, and leads to transcriptional repression of genes critical for myeloid differentiation and maturation. Conclusions Our results not only provide novel topological insights for the roles of PML-RARα in transforming myeloid cells into leukemia cells, but further uncover a topological framework of a molecular mechanism for oncogenic fusion proteins in cancers.