Possible Functions of Quadruplexes in the Genome

It is also worth highlighting that the COLlAl sequence is also believed to be a binding site for the transcription factor (TF) Spl. This TF, as well as a family of other TFs, binds G-rich sequences (or their C-rich converses). Another example is the TF huRNP which binds within the c-myc promoter 

Quadruplexes could also act purely as a structural feature, enabling easy recognition by proteins or other species. This model has been proposed for telomeric repeats, perhaps as a beads-on-a-string model of sequential folded quadruplexes. Other regions could also have such structural behaviours. 

Other possible physiological roles for quadruplexes, which have not yet been demonstrated experimentally, include roles in translation initiation or splicing. Many others can be proposed. 

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