DNA sequences of the NHE G-rich strand from the c-myc promoter and its derivatives: (a) Pu27, the 27-nt wild-type sequence; (b) myc-2345, a “chair” derivative5 containing G-tracks number 2, 3, 4, and 5; and (c) myc-1245, a “basket” derivative5 containing G-tracks number 1, 2, 4, and 5; the G-track number 3 is substituted by T4.