富含鸟嘌呤的核酸序列可形成G-四链体结构，该结构广泛分布于人的基因组中并参与基因调控。TRF2是庇护蛋白复合物的亚基之一，在参与保护端粒末端过程中起到重要作用。该蛋白可以结合端粒DNA和端粒非编码RNA(TERRA)序列，且结合过程特异性依赖于G-四链体这种高级结构。TRF2基因中也存在可形成G-四链体的序列（PQS序列），我们在前期研究中发现TRF2与自身PQS序列形成的G-四链体结合。故本项目拟研究TRF2通过和自身基因PQS序列形成的G-四链体相互作用、调控TRF2基因本身的过程，探索G-四链体结构在此过程中的作用。研究G-四链体介导的TRF2基因自调控机制，将有助于理解TRF2在保护端粒末端和T-loop形成过程中的重要生物学意义。

G-quadruplex formed by guanine-rich nucleic acid is widely dispersed in the human genome and is involved in the gene regulation. TRF2 is one subunit of the Shelterin complex and plays a significant role in protecting the end of telomere. TRF2 specifically interacts, via G-quadruplex formation, with telomeric DNA and RNA sequence. There are Potential G-Quadruplex-forming Sequences (PQS) among the TRF2 gene. We previously discovered that TRF2 interacted with the G-quadruplex formed by the PQS in the TRF2 gene itself. It is expected that the interaction between them may provide possibility of the TRF2 gene's auto-regulation. The study on the mechanism of the G-quadruplex mediated auto-regulation of TRF2 will facilitate better understanding the biological significance of TRF2 during protecting telomeric end and T-loop formation.