ArticleThe EMBO journal1995
The sorting signal of cytochrome b2 promotes early divergence from the general mitochondrial import pathway and restricts the unfoldase activity of matrix Hsp70.
Article in The EMBO journal, 1995. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
15 citing papers in PubMed, 56 citations in OpenAlex.
- mtHsp70 chaperone converts mitochondrial proteostasis stress into impaired protein import.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Article
- Interactions of amyloidogenic proteins with mitochondrial protein import machinery in aging-related neurodegenerative diseases.Frontiers in physiology · 2023Review
- Article
- Proteomic analysis of the yeast mitochondrial outer membrane reveals accumulation of a subclass of preproteins.Molecular biology of the cell · 2006Article
- Apocytochrome c requires the TOM complex for translocation across the mitochondrial outer membrane.The EMBO journal · 2001Article
- Membrane potential-driven protein import into mitochondria. The sorting sequence of cytochrome b(2) modulates the deltapsi-dependence of translocation of the matrix-targeting sequence.Molecular biology of the cell · 2000Article
- Protein unfolding by mitochondria. The Hsp70 import motor.EMBO reports · 2000Review
- Two distinct mechanisms drive protein translocation across the mitochondrial outer membrane in the late step of the cytochrome b(2) import pathway.Proceedings of the National Academy of Sciences of the United States of America · 1999Article
- Biogenesis of Tim proteins of the mitochondrial carrier import pathway: differential targeting mechanisms and crossing over with the main import pathway.Molecular biology of the cell · 1999Article
- Unfolding of preproteins upon import into mitochondria.The EMBO journal · 1998Article
- Active unfolding of precursor proteins during mitochondrial protein import.The EMBO journal · 1997Article
- Analysis of the sorting signals directing NADH-cytochrome b5 reductase to two locations within yeast mitochondria.Molecular and cellular biology · 1997Article
- Multiple interactions of components mediating preprotein translocation across the inner mitochondrial membrane.The EMBO journal · 1997Article
- Tom7 modulates the dynamics of the mitochondrial outer membrane translocase and plays a pathway-related role in protein import.The EMBO journal · 1996Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Cytochrome b2 is imported into mitochondria and sorted to the intermembrane space by a bipartite N-terminal presequence, which is a matrix targeting sequenced followed by an intermembrane space sorting signal. The N-terminus of the mature protein forms a folded heme binding domain that depends on the unfoldase function of matrix (mt) Hsp70 for import. We report that the distance between the presequence and the heme binding domain is critical for the ability of mt-Hsp70 to promote import of the domain. Hybrid proteins with 40 or more amino acids between the presequence and the heme binding domain are arrested in the import machinery. The translocation arrest can be overcome by unfolding of the preprotein or by inactivation of the intermembrane space sorting signal. Moreover, the sorting signal prevents backsliding of the precursor polypeptide in the import site in the initial import step, when the signal has not made contact with the matrix. The results indicate that the sorting signal interacts with component(s) of the inner membrane/intermembrane space during the initial import step and promotes an early divergence of b2 preproteins from the general matrix import pathway, precluding an unfolding role for mt-Hsp70 in the translocation of most of the mature portions of a preprotein. We propose a sorting model of cytochrome b2 which explains the apparently divergent previous results by a unifying hypothesis.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.