Fig. 4
From: In vivo dynamics and regulation of DNA G-quadruplex structures in mammals
Effects of eG4 dynamics on telomeres. A Folded telomere eG4s (orange) and TERRA RNA eG4s (green) together serve as a scaffold to recruit FUS protein and histone methyltransferase to maintain the state of telomere heterochromatin. B Normal telomere DNA replication requires telomere eG4s to be unfolded by the CST complex or RTEL1. C Telomere eG4s are folded into different structures and regulate telomere extension. Antiparallel intramolecular eG4s inhibit telomerase binding and telomere extension (left). Parallel intermolecular telomere eG4s promote telomerase-mediated telomere extension (right)