2CIU

Structure of the IMS domain of the mitochondrial import protein Tim21 from S. cerevisiae

Summary for 2CIU

• Entry DOI: 10.2210/pdb2ciu/pdb
• Descriptor: IMPORT INNER MEMBRANE TRANSLOCASE SUBUNIT TIM21 MITOCHONDRIAL (2 entities in total)
• Functional Keywords: mitochondrial import, inner membrane, membrane, mitochondrion, protein transport, transit peptide, translocation, transmembrane, transport
• Biological source: SACCHAROMYCES CEREVISIAE (BAKER'S YEAST)
• Cellular location: Mitochondrion inner membrane; Single-pass membrane protein: P53220
• Total number of polymer chains: 1
• Total formula weight: 14763.00

Authors

Albrecht, R.,Zeth, K.,Rehling, P.,Pfanner, N. (deposition date: 2006-03-24, release date: 2006-12-21, Last modification date: 2024-05-08)

Primary citation

Albrecht, R.,Rehling, P.,Chacinska, A.,Brix, J.,Cadamuro, S.A.,Volkmer, R.,Guiard, B.,Pfanner, N.,Zeth, K.
The Tim21 Binding Domain Connects the Preprotein Translocases of Both Mitochondrial Membranes
Embo Rep., 7:1233-, 2006

PubMed Abstract: Proteins destined for the mitochondrial matrix are imported by the translocase of the outer membrane--the TOM complex--and the presequence translocase of the inner membrane--the TIM23 complex. At present, there is no structural information on components of the presequence translocase. Tim21, a subunit of the presequence translocase consisting of a membrane anchor and a carboxy-terminal domain exposed to the intermembrane space, directly connects the TOM and TIM23 complexes by binding to the intermembrane space domain of the Tom22 receptor. We crystallized the binding domain of Tim21 of Saccharomyces cerevisiae and determined its structure at 1.6 A resolution. The Tim21 structure represents a new alpha/beta-mixed protein fold with two alpha-helices flanked by an extended eight-stranded beta-sheet. We also identified a core sequence of Tom22 that binds to Tim21. Furthermore, negatively charged amino-acid residues of Tom22 are important for binding to Tim21. Here we suggest a mechanism for the TOM-TIM interaction.

PubMed: 17099692
DOI: 10.1038/SJ.EMBOR.7400828

Experimental method

X-RAY DIFFRACTION (1.6 Å)