Greehey Children’s Cancer Research Institute, Mays Cancer Center, Department of Molecular Medicine, UT Health Science Center San Antonio, 8403 Floyd Curl Drive, San Antonio, TX 78229-3000, USA
Yohei Niikura
Greehey Children’s Cancer Research Institute, Mays Cancer Center, Department of Molecular Medicine, UT Health Science Center San Antonio, 8403 Floyd Curl Drive, San Antonio, TX 78229-3000, USA
Argentina Becker
Greehey Children’s Cancer Research Institute, Mays Cancer Center, Department of Molecular Medicine, UT Health Science Center San Antonio, 8403 Floyd Curl Drive, San Antonio, TX 78229-3000, USA
Peter J. Houghton
Greehey Children’s Cancer Research Institute, Mays Cancer Center, Department of Molecular Medicine, UT Health Science Center San Antonio, 8403 Floyd Curl Drive, San Antonio, TX 78229-3000, USA
Katsumi Kitagawa
Greehey Children’s Cancer Research Institute, Mays Cancer Center, Department of Molecular Medicine, UT Health Science Center San Antonio, 8403 Floyd Curl Drive, San Antonio, TX 78229-3000, USA; Corresponding author
Summary: The centromere is essential for ensuring high-fidelity transmission of chromosomes. CENP-A, the centromeric histone H3 variant, is thought to be the epigenetic mark of centromere identity. CENP-A deposition at the centromere is crucial for proper centromere function and inheritance. Despite its importance, the precise mechanism responsible for maintenance of centromere position remains obscure. Here, we report a mechanism to maintain centromere identity. We demonstrate that CENP-A interacts with EWSR1 (Ewing sarcoma breakpoint region 1) and EWSR1-FLI1 (the oncogenic fusion protein in Ewing sarcoma). EWSR1 is required for maintaining CENP-A at the centromere in interphase cells. EWSR1 and EWSR1-FLI1 bind CENP-A through the SYGQ2 region within the prion-like domain, important for phase separation. EWSR1 binds to R-loops through its RNA-recognition motif in vitro. Both the domain and motif are required for maintaining CENP-A at the centromere. Therefore, we conclude that EWSR1 guards CENP-A in centromeric chromatins by binding to centromeric RNA.
