Crystal Structure of the N-Terminal RNA Recognition Motif of mRNA Decay Regulator AUF1

Figure 4

Comparison of the tandem RRM conformations. (a) Sequence alignment of tandem RRM1 and RRM2 regions of AUF1, HuR, and hnRNP A1. Conserved residues are presented in either orange or yellow backgrounds depending on their degree of conservation. The linker between RRM1 and RRM2 is highlighted in pink and also indicated under the sequences. The secondary-structure element of AUF1 is shown. (b) Stereo diagram of overlay of dimeric AUF1-RRM1 and hnRNP A1 in complex with telomeric DNA fragment (PDB entry 2UP1). The colors of the dimeric AUF1-RRM1 are the same as in Figure 2(b). The hnRNP A1 and DNA are colored gray and orange. The linker between RRMs is shown in magenta. (c) Stereo diagram of overlay of dimeric AUF1-RRM1 and HuR in complex with the AU-rich RNA fragment (PDB entry 4ED5). The colors of the dimeric AUF1-RRM1 are the same as in Figure 2(b). HuR and RNA are gray and orange, respectively. The linker between RRMs is shown in magenta. (d) Overlay of dimeric AUF1-RRM1 and HuR apo (PDB entry 4EGL). The 60° rotated view along the -axis is shown on the right panel. The colors of the dimeric AUF1-RRM1 are the same as in Figure 2(b). HuR is colored gray. The linker between RRMs is shown in magenta.

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