| 2001 |
IMMP2L encodes the human homologue of yeast mitochondrial inner membrane peptidase subunit 2; the gene spans 860 kb, encompasses six exons, and produces a 1,522-bp transcript. It was identified as a novel gene disrupted by chromosomal breakpoints at 7q31 in a Tourette syndrome patient. |
cDNA cloning, Southern blot hybridization, FISH analysis |
American journal of human genetics |
Medium |
11254443
|
| 2007 |
IMMP2L (Immp2l) is required for signal peptide processing of mitochondrial proteins cytochrome c1 (CYC1) and glycerol-3-phosphate dehydrogenase 2 (GPD2). Mutation of Immp2l impairs this processing, causing mitochondrial hyperpolarization, elevated superoxide generation, and higher ATP levels, leading to reproductive defects linked to decreased nitric oxide bioavailability and increased ROS. |
Transgenic insertional mutagenesis (Immp2lTg(Tyr)979Ove mouse), mitochondrial functional assays (membrane potential, superoxide measurement, ATP levels), protein processing analysis |
Biology of reproduction |
High |
18094351
|
| 2011 |
Immp2l mutation impairs processing of CYC1 and GPD2 signal peptides, elevates mitochondrial superoxide in multiple organs, and causes accelerated aging phenotypes (sarcopenia, kyphosis, ataxia, loss of subcutaneous fat). Adipose-derived stromal cells from mutants show impaired proliferation and increased oxidative stress, linking mitochondrial ROS to adult stem cell dysfunction and age-associated disorders. |
Immp2l mutant mouse model, oxidative stress measurements (superoxide dismutase expression, protein carbonylation), colony formation assay, adipogenic differentiation assay |
Aging cell |
High |
21332923
|
| 2012 |
Immp2l mutation impairs processing of CYC1 and GPD2 signal peptides, generating elevated mitochondrial superoxide that causes age-dependent spermatogenic damage. Protein carbonyl content is elevated only in old (13-month) mutant testes coincident with spermatogenic failure; mtDNA mutation rate is unchanged, excluding a major role for mtDNA mutation in this ROS-mediated damage. |
Immp2l mutant mouse model, protein carbonyl assay, TUNEL apoptosis assay, mtDNA mutation rate analysis, antioxidant enzyme expression analysis |
Free radical biology & medicine |
High |
22569411
|
| 2014 |
Despite impaired signal peptide cleavage of CYC1 and GPD2, the intermediate (unprocessed) forms of these proteins retain normal expression levels and enzymatic function in Immp2l mutant mice. Mitochondrial respiration is not diminished in isolated mitochondria or cells from mutant mice, indicating that respiratory deficiency is NOT the cause of Immp2l mutant phenotypes. |
Immp2l mutant mouse model, enzymatic activity assays for GPD2 and CYC1, mitochondrial respiration measurement (Seahorse or equivalent), protein expression analysis |
Redox biology |
Medium |
25460737
|
| 2015 |
Immp2l mutation causes age-dependent degeneration specifically of cerebellar granule neurons (not Purkinje cells or molecular layer cells) in old mice (>16 months), accompanied by increased oxidative stress markers (HNE, nitrotyrosine, protein carbonyl). Treatment with the mitochondria-targeted antioxidant SkQ1 from 6 weeks to 21 months prevented granule neuron loss and restored SOD2 and VDAC1 expression, demonstrating a causal role for mitochondrial oxidative stress in this neurodegeneration. |
Immp2l mutant mouse model, histology/immunohistochemistry, SkQ1 antioxidant treatment, immunofluorescence for SOD2 and VDAC1, oxidative stress marker quantification |
Aging cell |
High |
26616244
|
| 2016 |
IMMP2L transcription in human primary astrocytes requires Topoisomerase I. IMMP2L knockdown dysregulates genes involved in CNS development, and the transcriptional response partially overlaps with that induced by mitochondrial complex III inhibition. |
IMMP2L knockdown in human primary astrocytes, Topoisomerase I inhibition, transcriptome analysis (RNA-seq or microarray) |
Biochemical and biophysical research communications |
Medium |
27932244
|
| 2018 |
IMMP2L processes and activates at least two substrates: mitochondrial metabolic enzyme GPD2 and cell death regulator apoptosis-inducing factor (AIF). Shutdown of IMMP2L-GPD2 signaling reprograms mitochondria-associated redox status and phospholipid metabolism, while shutdown of IMMP2L-AIF signaling blocks cell death under oxidative stress. Coordinated loss of both axes drives the cellular senescence program. |
Multi-omics approaches, IMMP2L knockdown/knockout cell models, metabolic profiling, senescence assays, identification of GPD2 and AIF as substrates |
Cell research |
High |
29808012
|
| 2020 |
In Immp2l-/- mice, follicle development is arrested at the secondary follicle stage due to mitochondrial dysfunction. The mechanism involves increased ROS, decreased estrogen levels, and altered Wnt/β-catenin and steroid hormone synthesis (CYP19A1) pathway gene expression. In vitro Immp2l knockdown in granulosa cells suppresses Wnt16, increases β-catenin, and decreases CYP19A1/estrogen, confirming the ROS-Wnt/β-catenin-estrogen pathway axis. Melatonin (antioxidant) treatment reverses these effects. |
Immp2l-/- mouse model, in vitro granulosa cell Immp2l knockdown, ROS measurement, hormone assays, Western blot/gene expression for Wnt pathway components, melatonin rescue experiment |
Endocrinology |
High |
32652035
|
| 2023 |
IMMP2L/Immp2l cleaves the mitochondrial transit peptide from GPD2 (and CYC1), and this processing enhances GPD2 homodimeric structure and its respiratory function. In Immp2l-/- KO mice, glycerol-3-phosphate (G3P)-driven mitochondrial respiration is decreased (~20% female, ~7% male), nonmitochondrial respiration is dramatically lowered, AlphaFold2-Multimer structural modeling predicts altered Cyc1-cytochrome b interaction in Complex III and disrupted GPD2 homodimer structure. Primary MEF cells show ~27% decrease in total respiration and ~50% decrease in nonmitochondrial respiration. |
Immp2l-/- KO mouse model, substrate-specific mitochondrial respiration assays (G3P, succinate, glutamate), AlphaFold2-Multimer structural prediction, EchoMRI, mitoROS measurement, primary MEF cell lines |
International journal of molecular sciences |
Medium |
38256063
|
| 2023 |
In Immp2l-/- KO mice (complete knockout devoid of peptidase activity), ROS levels are significantly LOWERED (not elevated), and mice are fully fertile with no age-related ataxia or neurodegeneration. This contrasts with the elevated ROS phenotype of the earlier truncated Immp2l mutant (intragenic deletion) mouse model, suggesting that oxidative stress phenotypes previously attributed to IMMP2L loss may be specific to the truncated protein rather than complete absence of peptidase activity. |
Immp2l-/- KO mouse model, mitoROS measurement, fertility assessment, electron microscopy for neurodegeneration, MitoQ antioxidant treatment |
Genes |
Medium |
37761857
|
| 2024 |
In Immp2l-knockout granulosa cells, STAT1 expression is increased and controlled by S-glutathionylation and S-nitrosylation (not phosphorylation), as shown by Co-IP. Immp2l deficiency impairs UPRmt (unfolded protein response of mitochondria) and activates HIF1α/BNIP3-mediated mitophagy, but mitophagy is blocked due to reduced fusion of mitophagosomes and lysosomes, leading to mitochondria accumulation, increased ROS, and granulosa cell senescence. |
Immp2l knockout mouse/cell model, Co-IP for STAT1 modifications, Western blot for UPRmt and mitophagy pathway components, mitochondrial function assays, senescence assays, enocyanin treatment rescue |
International journal of molecular sciences |
Medium |
39456903
|
| 2025 |
Immp2l knockout induces mtDNA leakage from mitochondria into the cytoplasm via CyPD40 (inner membrane pore) and VDAC1 (outer membrane pore), both of which are upregulated. Cytoplasmic mtDNA activates cGAS-STING signaling and downstream interferon-stimulated genes, promoting SASP (senescence-associated secretory phenotype) and granulosa cell senescence. TFAM knockdown (siRNA) reduces cytoplasmic mtDNA and inhibits cGAS-STING activation, confirming TFAM-mediated mtDNA stability as a key regulatory node. |
Immp2l KO mouse/granulosa cell model, siRNA knockdown of TFAM, Western blot for cGAS-STING pathway components and CyPD40/VDAC1, cytoplasmic mtDNA measurement, SASP assays, PCB2 treatment rescue |
International journal of biological macromolecules |
Medium |
40120895
|
| 2023 |
Immp2l+/- (heterozygous) mutation leads to mitochondrial membrane potential depolarization and suppression of mitochondrial respiratory Complex III activity after cerebral ischemia-reperfusion injury. This is accompanied by caspase-3 activation and AIF nuclear translocation, indicating activation of mitochondria-mediated apoptosis pathways. |
Immp2l+/- mouse model, middle cerebral artery occlusion (MCAO) ischemia-reperfusion model, JC-1 mitochondrial membrane potential assay, Complex III activity assay, caspase-3 Western blot, AIF nuclear translocation assay |
Current medical science |
Medium |
37243806
|