Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Automatic assignment of GO terms using logical inference, based on on inter-ontology links
Import of carrier proteins into the mitochondrial inner membrane mediated by Tim22.
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First identification of Tim22 as required for import of ADP/ATP carrier family members into the mitochondrial inner membrane.
"Tim22 is required for the import of proteins of the mitochondrial ADP/ATP carrier (AAC) family into the inner membrane"
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Tim22 is in a complex distinct from the Tim23-Tim17 complex, and import of carrier proteins is independent of Tim23.
"Import of proteins of the AAC family is independent of Tim23, and import of matrix targeting signals containing preproteins is independent of Tim22"
Tim18p is a new component of the Tim54p-Tim22p translocon in the mitochondrial inner membrane.
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Tim18p identified as a new subunit of the Tim54p-Tim22p complex by genetic suppression and biochemical co-purification.
"Tim54p and Tim22p can be coimmune precipitated with the Tim18 protein; and Tim18p, along with Tim54p and Tim22p, is detected in an approximately 300-kDa complex after blue native electrophoresis"
Tim18p, a new subunit of the TIM22 complex that mediates insertion of imported proteins into the yeast mitochondrial inner membrane.
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The TIM22 complex contains integral membrane subunits Tim22p and Tim54p, plus peripheral subunits Tim9p, Tim10p, and Tim12p.
"The TIM22 complex contains the peripheral subunits Tim9p, Tim10p, and Tim12p and the integral membrane subunits Tim22p and Tim54p"
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Tim18p functions in assembly and stabilization of the TIM22 complex but does not directly participate in protein insertion.
"Tim18p functions in the assembly and stabilization of the TIM22 complex but does not directly participate in protein insertion into the inner membrane"
Tim22, the essential core of the mitochondrial protein insertion complex, forms a voltage-activated and signal-gated channel.
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Tim22 is the only essential membrane-integrated subunit of the protein insertion complex and forms a channel when reconstituted.
"Tim22 is the only essential membrane-integrated subunit of the complex. Reconstituted Tim22 forms a hydrophilic, high-conductance channel with distinct opening states and pore diameters"
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The Tim22 channel is voltage-activated and specifically gated by internal targeting signals, not by N-terminal presequences.
"The channel is voltage-activated and specifically responds to an internal targeting signal, but not to presequences"
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Tim22 combines signal recognition, channel formation, and energy transduction in one component.
"a protein insertion complex can combine three essential functions, signal recognition, channel formation, and energy transduction, in one central component"
Protein insertion into the mitochondrial inner membrane by a twin-pore translocase.
Toward the complete yeast mitochondrial proteome: multidimensional separation techniques for mitochondrial proteomics.
The Tim21 binding domain connects the preprotein translocases of both mitochondrial membranes.
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Tim21 connects the TOM and TIM23 complexes. TIM22-Tim21 interaction detected by IntAct.
"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"
Quantitative variations of the mitochondrial proteome and phosphoproteome during fermentative and respiratory growth in Saccharomyces cerevisiae.
Conserved regions of budding yeast Tim22 have a role in structural organization of the carrier translocase.
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The IMS and TM4 regions of Tim22 are critically required for interactions with Tim54, Tim18, and Sdh3, maintaining the functional architecture of the TIM22 translocase.
"the intermembrane space (IMS) and transmembrane 4 (TM4) regions of Tim22 are critically required for interactions with the membrane-embedded subunits, including Tim54, Tim18, and Sdh3, and thereby maintain the functional architecture of the TIM22 translocase"
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TM1 and TM2 regions mediate Tim18 interaction; TM3 is required for Sdh3 interaction.
"the TM1 and TM2 regions of Tim22 are important for association with Tim18, whereas TM3 is exclusively required for the interaction with Sdh3"
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Impairment of TIM22 complex assembly affects translocase activity, mitochondrial network integrity, and viability.
"impairment of TIM22 complex assembly influences its translocase activity, the mitochondrial network, and the viability of cells lacking mitochondrial DNA"
Structure of the mitochondrial TIM22 complex from yeast
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Cryo-EM structure of the endogenous yeast TIM22 complex at 3.8 angstrom resolution reveals a 7-subunit architecture with Tim22 possessing 4 transmembrane helices, a C42-C141 disulfide bond, and conserved charged residues (E140, D190, K127, K169) critical for function.
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The hexameric small-Tim ring (Tim9/Tim10/Tim12) is tilted approximately 45 degrees relative to the membrane plane.
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The captured cryo-EM state does not display a clear open translocation pore, suggesting Tim22 may operate via conformationally gated states or an insertase-like mechanism that alters local bilayer properties.
Functional crosstalk between the TIM22 complex and YME1 machinery maintains mitochondrial proteostasis and integrity
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Yme1 i-AAA protease is required for stability of the TIM22 complex and for proteostasis of TIM22 pathway substrates; a small non-stoichiometric pool of Yme1 associates transiently with TIM22.
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Loss of Yme1 leads to accumulation of TIM22 substrates outside mitochondria, altered mitochondrial morphology, and compromised respiration; reducing TIM22 activity (e.g., deleting Tim18) reduced cargo accumulation in yme1-delta contexts.
Role of Yme1 in mitochondrial protein homeostasis: from regulation of protein import, OXPHOS function to lipid synthesis and mitochondrial dynamics
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Mini-review synthesizing evidence that Yme1 contributes to TIM22 pathway robustness, including degradation of misfolded small Tim chaperones with differential susceptibility of Tim10 vs Tim9, and that loss of Yme1 reduces TIM22 stability and import efficiency especially under heat stress.
Identification of MIMAS, a multifunctional mega-assembly integrating metabolic and respiratory biogenesis factors of mitochondria
TOM40:TOM70 complex translocates proteins from the cytosol to the mitochondrial intermembrane space
TIM22 complex inserts proteins into inner membrane
TIM9:TIM10 binds hydrophobic proteins