Regulation of I𝜅B𝛼 Function and NF-𝜅B Signaling: AEBP1 Is a Novel Proinflammatory Mediator in Macrophages

Figure 1

Structural Organization of NF-𝜅B/Rel and I𝜅B Proteins. (a) A schematic representation of some members of the Rel family of proteins. Members of this family contain a unique, highly conserved Rel homology domain (RHD) towards the N-terminus, and this domain carries a nuclear localization signal (NLS). Most members of the Rel family contain a C-terminally located transactivation domain (TAD) that is important for optimal transcriptional activity. RelB is a structurally unique member of the NF-𝜅B protein family in that it contains a leucine zipper-like (LZ) region at its N-terminus. (b) A schematic representation of some members of the I𝜅B family of proteins, which are uniquely characterized by the presence of 30-33-amino acid ankyrin (ANK) repeats. At least for I𝜅B𝛼 and I𝜅B𝛽 the most well-characterized members of the I𝜅B family, there are two conserved serine residues at the N-terminus preceding the first ANK repeat. Phosphorylation of these two serine residues is known to be crucial for signaling I𝜅B proteins for ubiquitination and proteolytic degradation. At the C-terminus of I𝜅B proteins, there is a region rich with proline, glutamate, serine, and threonine residues, and hence, it is named the PEST domain. The number of amino acid residues within the indicated proteins in mouse is shown.

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