Tingfang Li, Miaomiao Zhang, Yanjing Li, Xinyu Han, Lu Tang, Tengfei Ma, Xiaotong Zhao, Rui Zhao, Yuwen Wang, Xue Bai, Kai Zhang, Xin Geng, Lei Sui, Xuyang Feng, Qiang Zhang, Yang Zhao, Yang Liu, Jason A Stewart, Feng Wang
Human CST (CTC1-STN1-TEN1) is a ssDNA-binding complex that interacts with the replisome to aid in stalled fork rescue. We previously found that CST promotes telomere replication to maintain genomic integrity via G-quadruplex (G4) resolution. However, the detailed mechanism by which CST resolves G4s in vivo and whether additional factors are involved remains unclear. Here, we identify RECQ4 as a novel CST-interacting partner and show that RECQ4 can unwind G4 structures in vitro using a FRET assay. Moreover, G4s accumulate at the telomere after RECQ4 depletion, resulting in telomere dysfunction, including the formation of MTSs, SFEs, and TIFs, suggesting that RECQ4 is crucial for telomere integrity...
July 26, 2023: EMBO Reports