Fig. 3.

The IP₅ 2-K family. (A) Structural alignment of At-IP₅ 2-K with IP₅ 2-Ks from other sources (Hs:human, Rn:rat, and Sc:yeast). Secondary elements are shown and named on top, and colored in the same code. Zn binding residues from At-IP₅ 2-K are inside green squares. Conserved residues are gray squared and motifs are shown below. Residues shown in dark green and blue are ATP and inositide ligands, respectively. The IP₃ 3-K structural elements conserved with IP₅ 2-K and their sequence are shown below. (B) Schematic domain representation of IP₅ 2-Ks vs. the IPK family (IP₃ 3-K, IP₆ Ks and IPm Ks). The black rod represents α4, which is conserved in all IPKs, and is similar to PKs αC. The IP₅ 2-K G-loop, R40, and conserved motifs are marked on top, and the equivalent IPK regions are shown.