Early growth response 1 (EGR-1) is a transcriptional regulator of mitochondrial carrier homolog 1 (MTCH 1)/presenilin 1-associated protein (PSAP)

Identification of MTCH1 as a novel prognostic indicator and therapeutic target in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) emerges as the third leading cause of cancer mortality, contributing to approximately 830,000 deaths annually. The mechanisms driving its pathogenesis remain largely elusive. Through bioinformatic scrutiny, Mitochondrial Carrier 1 (MTCH1), a component of the mitochondrial carrier family, has been pinpointed as potentially pivotal in HCC evolution. Examination of The Cancer Genome Atlas (TCGA) database indicated a pronounced increase in MTCH1 expression within HCC tissues versus normal liver counterparts. Subsequent analyses, utilizing both Kaplan-Meier mapper and Gene Expression Profiling Interactive Analysis (GEPIA) datasets, associated elevated MTCH1 levels with reduced overall survival (OS) and disease-free survival (DFS). Complementary in vitro assessments confirmed that MTCH1 downregulation suppresses HCC cell proliferation and notably diminishes HCC xenograft tumor growth in murine models. Additional explorations, including Gene Set Enrichment Analysis (GSEA), STRING database interrogation, and quantitative PCR (qPCR) experiments, suggest MTCH1's involvement in HCC progression via the CDK-RB-E2F signaling axis. Collectively, these insights endorse MTCH1 as a promising therapeutic target for HCC, underscoring its significance in the disease's molecular framework and potential treatment innovation.

ATAD3A has a scaffolding role regulating mitochondria inner membrane structure and protein assembly

The ATPase Family AAA Domain Containing 3A (ATAD3A), is a mitochondrial inner membrane protein conserved in metazoans. ATAD3A has been associated with several mitochondrial functions, including nucleoid organization, cholesterol metabolism, and mitochondrial translation. To address its primary role, we generated a neuronal-specific conditional knockout (Atad3 nKO) mouse model, which developed a severe encephalopathy by 5 months of age. Pre-symptomatic mice showed aberrant mitochondrial cristae morphogenesis in the cortex as early as 2 months. Using a multi-omics approach in the CNS of 2-to-3-month-old mice, we found early alterations in the organelle membrane structure. We also show that human ATAD3A associates with different components of the inner membrane, including OXPHOS complex I, Letm1, and prohibitin complexes. Stochastic Optical Reconstruction Microscopy (STORM) shows that ATAD3A is regularly distributed along the inner mitochondrial membrane, suggesting a critical structural role in inner mitochondrial membrane and its organization, most likely in an ATPase-dependent manner.

Arguello et al. show that deletion of the mitochondrial protein ATAD3 in neurons leads to neuronal loss and death. The earliest phenotype is disruption of the mitochondrial inner membrane structure; OXPHOS complexes are affected later. ATAD3 is regularly spaced and has several interactors at the inner membrane, including CI subunits.

Differential hippocampal protein expression between normal mice and mice with the perioperative neurocognitive disorder: a proteomic analysis

OBJECTIVES

To compare differential expression protein in hippocampal tissues from mice of perioperative neurocognitive disorder (PND) and normal control mice and to explore the possible mechanism of PND.

METHODS

Mice were randomly divided into a PND group (n = 9) and a control group (n = 9).The mice in the PND group were treated with open tibial fracture with intramedullary fixation under isoflurane anesthesia, while the mice in the control group received pure oxygen without surgery. The cognitive functions of the two groups were examined using Morris water maze experiment, Open field test and Fear conditioning test. The protein expression of the hippocampus of mice was analyzed by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore the principal functions of dysregulated proteins.

RESULTS

A total of 21 proteins were differentially expressed between PND and control mice on days 1, 3, and 7 after the operation. These proteins were involved in many pathological processes, such as neuroinflammatory responses, mitochondrial oxidative stress, impaired synaptic plasticity, and neuronal cell apoptosis. Also, the dysregulated proteins were involved in MAPK, AMPK, and ErbB signaling pathways.

CONCLUSION

The occurrence of PND could be attributed to multiple mechanisms.

Upregulation Mitochondrial Carrier 1 (MTCH1) Is Associated with Cell Proliferation, Invasion, and Migration of Liver Hepatocellular Carcinoma

Among the primary causes of cancer-associated death in the world, liver hepatocellular carcinoma (LIHC) ranks the third. LIHC is defined as the sixth most frequently diagnosed carcinoma. The gene mitochondrial carrier 1 (MTCH1) is a protein-coding gene. Recent research suggests that MTCH1 may be associated with some diseases. Here, our study attempts to explore the role and implication of MTCH1 in LIHC. Kaplan Meier Plotter and GEPIA (Gene Expression Profiling Interactive Analysis) databases were employed to determine the expression of MTCH1 and its correlation with prognostic status in LIHC patients. For the first time, our results suggested that MTCH1 was aberrantly expressed in human pan-cancer and highly expressed in LIHC. Its high expression was closely associated with metastasis of tumor, stage of cancer, and poor survival of patients. Then, through enrichment analysis, MTCH1 was found to be closely related to RNA splicing in LIHC. Subsequently, we conducted a series of functional experiments. PCR data showed that LIHC cell lines and samples are highly expressed MTCH1. CCK-8 (Cell Counting Kit-8) assays and Transwell assays indicated that silencing MTCH1 certainly suppressed cell proliferation, migration, and invasion. These findings shed the clue that MTCH1 could be regarded as the potential prognosis biomarker of LIHC and a promising therapeutic target for LIHC.

Early Growth Response Gene Upregulation in Epstein-Barr Virus (EBV)-Associated Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic multisystem disease exhibiting a variety of symptoms and affecting multiple systems. Psychological stress and virus infection are important. Virus infection may trigger the onset, and psychological stress may reactivate latent viruses, for example, Epstein-Barr virus (EBV). It has recently been reported that EBV induced gene 2 (EBI2) was upregulated in blood in a subset of ME/CFS patients. The purpose of this study was to determine whether the pattern of expression of early growth response (EGR) genes, important in EBV infection and which have also been found to be upregulated in blood of ME/CFS patients, paralleled that of EBI2. EGR gene upregulation was found to be closely associated with that of EBI2 in ME/CFS, providing further evidence in support of ongoing EBV reactivation in a subset of ME/CFS patients. EGR1, EGR2, and EGR3 are part of the cellular immediate early gene response and are important in EBV transcription, reactivation, and B lymphocyte transformation. EGR1 is a regulator of immune function, and is important in vascular homeostasis, psychological stress, connective tissue disease, mitochondrial function, all of which are relevant to ME/CFS. EGR2 and EGR3 are negative regulators of T lymphocytes and are important in systemic autoimmunity.

The multifunctional polydnavirus TnBVANK1 protein: impact on host apoptotic pathway

Toxoneuron nigriceps (Hymenoptera, Braconidae) is an endophagous parasitoid of the larval stages of the tobacco budworm, Heliothis virescens (Lepidoptera, Noctuidae). The bracovirus associated with this wasp (TnBV) is currently being studied. Several genes expressed in parasitised host larvae have been isolated and their possible roles partly elucidated. TnBVank1 encodes an ankyrin motif protein similar to insect and mammalian IκB, an inhibitor of the transcription nuclear factor κB (NF-κB). Here we show that, when TnBVank1 was stably expressed in polyclonal Drosophila S2 cells, apoptosis is induced. Furthermore, we observed the same effects in haemocytes of H. virescens larvae, after TnBVank1 in vivo transient transfection, and in haemocytes of parasitised larvae. Coimmunoprecipitation experiments showed that TnBVANK1 binds to ALG-2 interacting protein X (Alix/AIP1), an interactor of apoptosis-linked gene protein 2 (ALG-2). Using double-immunofluorescence labeling, we observed the potential colocalization of TnBVANK1 and Alix proteins in the cytoplasm of polyclonal S2 cells. When Alix was silenced by RNA interference, TnBVANK1 was no longer able to cause apoptosis in both S2 cells and H. virescens haemocytes. Collectively, these results indicate that TnBVANK1 induces apoptosis by interacting with Alix, suggesting a role of TnBVANK1 in the suppression of host immune response observed after parasitisation by T. nigriceps.