In several TRIAD proteins the N-terminal RING finger specifically binds K48 chain E2 conjugating enzymes, while the C-terminal RING finger binds the K63 enzymeyme, Ubc13.
A comparison of the footprints reveals that the presence of finger 7 affords protection at positions C19 and U55, the distal portion of helix II and the proximal portion of loop B. In addition, our footprints suggest that the central fingers bind in the same manner, whether in an isolated group or in the intact TFIIIA molecule.
Indeed, the structure analysis revealed that each CCCH zinc finger module from Zfp36l1 binds to the sequence UAUU; thus, the tandem zinc fingers bind to UAUU-UAUU.
However, peptide 10987 (containing the downstream-finger) binds to dsDNA with low co-operativity (αH=1.29 ± 0.35).
The JAZ zinc fingers bind equally well to a cellular dsRNA, pre-miR34a, as to viral dsRNA.
Snail family members Snail1 and Snail2 (Slug) act as transcriptional repressors when their fingers bind to E-box motifs (5'-CANNTG-3') in target promoters, including the E-cadherin gene (CDH1) promoter.
hunchback- and Ikaros-like transcription factors have a unique arrangement of C2H2 zinc fingers: four amino-terminal or middle C2H2 zinc fingers bind DNA (Molnar and Georgopoulos 1994), while two carboxy-terminal C2H2 zinc fingers mediate dimerization (McCarty et al. 2003).
Single zinc fingers bind to the RNA backbone without sequence specificity, forming complexes with contacts between the RNA minor groove and residues in the N-terminal β strands and between the major groove and residues in the helix kink helix motif.
Segal, D. J., Crotty, J. W., Bhakta, M. S., Barbas, C. F. & Horton, N. C. Structure of Aart, a designed six-finger zinc finger peptide, bound to DNA.
