3U0R

Helical repeat structure of apoptosis inhibitor 5 reveals protein-protein interaction modules

Summary for 3U0R

• Entry DOI: 10.2210/pdb3u0r/pdb
• Descriptor: Apoptosis inhibitor 5 (2 entities in total)
• Functional Keywords: heat repeat, armadillo repeat, lysine acetylation, apoptosis inhibitor
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus. Isoform 3: Cytoplasm: Q9BZZ5
• Total number of polymer chains: 1
• Total formula weight: 57121.20

Authors

Han, B.G.,Kim, K.H.,Jeong, K.C.,Cho, J.W.,Noh, K.H.,Kim, T.W.,Yoon, H.J.,Suh, S.W.,Lee, S.H.,Lee, B.I. (deposition date: 2011-09-29, release date: 2012-02-22, Last modification date: 2024-03-20)

Primary citation

Han, B.G.,Kim, K.H.,Lee, S.J.,Jeong, K.C.,Cho, J.W.,Noh, K.H.,Kim, T.W.,Kim, S.J.,Yoon, H.J.,Suh, S.W.,Lee, S.H.,Lee, B.I.
Helical repeat structure of apoptosis inhibitor 5 reveals protein-protein interaction modules.
J.Biol.Chem., 287:10727-10737, 2012

PubMed Abstract: Apoptosis inhibitor 5 (API5) is an anti-apoptotic protein that is up-regulated in various cancer cells. Here, we present the crystal structure of human API5. API5 exhibits an elongated all α-helical structure. The N-terminal half of API5 is similar to the HEAT repeat and the C-terminal half is similar to the ARM (Armadillo-like) repeat. HEAT and ARM repeats have been implicated in protein-protein interactions, suggesting that the cellular roles of API5 may be to mediate protein-protein interactions. Various components of multiprotein complexes have been identified as API5-interacting protein partners, suggesting that API5 may act as a scaffold for multiprotein complexes. API5 exists as a monomer, and the functionally important heptad leucine repeat does not exhibit the predicted a dimeric leucine zipper. Additionally, Lys-251, which can be acetylated in cells, plays important roles in the inhibition of apoptosis under serum deprivation conditions. The acetylation of this lysine also affects the stability of API5 in cells.

PubMed: 22334682
DOI: 10.1074/jbc.M111.317594

Experimental method

X-RAY DIFFRACTION (2.5 Å)