1Y1U

Structure of unphosphorylated STAT5a

Summary for 1Y1U

• Entry DOI: 10.2210/pdb1y1u/pdb
• Descriptor: Signal transducer and activator of transcription 5A (1 entity in total)
• Functional Keywords: activator, stat, dna-binding, sh2 domain, transcription regulation, signaling protein
• Biological source: Mus musculus (house mouse)
• Cellular location: Cytoplasm : P42230
• Total number of polymer chains: 3
• Total formula weight: 201778.24

Authors

Neculai, D.,Neculai, A.M.,Verrier, S.,Straub, K.,Klumpp, K.,Pfitzner, E.,Becker, S. (deposition date: 2004-11-19, release date: 2005-10-04, Last modification date: 2023-10-25)

Primary citation

Neculai, D.,Neculai, A.M.,Verrier, S.,Straub, K.,Klumpp, K.,Pfitzner, E.,Becker, S.
Structure of the unphosphorylated STAT5a dimer
J.Biol.Chem., 280:40782-40787, 2005

PubMed Abstract: STAT proteins have the function of signaling from the cell membrane into the nucleus, where they regulate gene transcription. Latent mammalian STAT proteins can form dimers in the cytoplasm even before receptor-mediated activation by specific tyrosine phosphorylation. Here we describe the 3.21-A crystal structure of an unphosphorylated STAT5a homodimer lacking the N-terminal domain as well as the C-terminal transactivation domain. The overall structure of this fragment is very similar to phosphorylated STATs. However, important differences exist in the dimerization mode. Although the interface between phosphorylated STATs is mediated by their Src-homology 2 domains, the unphosphorylated STAT5a fragment dimerizes in a completely different manner via interactions between their beta-barrel and four-helix bundle domains. The STAT4 N-terminal domain dimer can be docked onto this STAT5a core fragment dimer based on shape and charge complementarities. The separation of the dimeric arrangement, taking place upon activation and nuclear translocation of STAT5a, is demonstrated by fluorescence resonance energy transfer experiments in living cells.

PubMed: 16192273
DOI: 10.1074/jbc.M507682200

Experimental method

X-RAY DIFFRACTION (3.21 Å)