... formed between the 3¢-end of each block; and (c) 5¢-to-3¢, in which the stacking interface isformed between the 5¢-end of one block and the 3¢-end of the other. In the ‘same-direction stacking’ ... the ends of the G-tetrad core, (b) groove binding, (c)taking place of one or more strands in the core, (d)interacting with the backbone (core and loops), and (e)interacting with the loop bases. ... three G-tracts of one strand and only the 3¢-end G -tract of the other strand [30] (Fig. 3D). The core of this structure, called the (3 + 1) core, hasthree strands oriented in one direction and one...