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Acta Neuropathologica Communications Jun 2024
Topics: Humans; Central Nervous System Neoplasms; Male; Child; Female; Oncogene Proteins, Fusion; Repressor Proteins
PubMed: 38926750
DOI: 10.1186/s40478-024-01824-w -
Microbial Cell Factories Jun 2024Currently, industrial fermentation of Botrytis cinerea is a significant source of abscisic acid (ABA). The crucial role of ABA in plants and its wide range of...
BACKGROUND
Currently, industrial fermentation of Botrytis cinerea is a significant source of abscisic acid (ABA). The crucial role of ABA in plants and its wide range of applications in agricultural production have resulted in the constant discovery of new derivatives and analogues. While modifying the ABA synthesis pathway of existing strains to produce ABA derivatives is a viable option, it is hindered by the limited synthesis capacity of these strains, which hinders further development and application.
RESULTS
In this study, we knocked out the bcaba4 gene of B. cinerea TB-31 to obtain the 1',4'-trans-ABA-diol producing strain ZX2. We then studied the fermentation broth of the batch-fed fermentation of the ZX2 strain using metabolomic analysis. The results showed significant accumulation of 3-hydroxy-3-methylglutaric acid, mevalonic acid, and mevalonolactone during the fermentation process, indicating potential rate-limiting steps in the 1',4'-trans-ABA-diol synthesis pathway. This may be hindering the flow of the synthetic pathway. Additionally, analysis of the transcript levels of terpene synthesis pathway genes in this strain revealed a correlation between the bchmgr, bcerg12, and bcaba1-3 genes and 1',4'-trans-ABA-diol synthesis. To further increase the yield of 1',4'-trans-ABA-diol, we constructed a pCBg418 plasmid suitable for the Agrobacterium tumefaciens-mediated transformation (ATMT) system and transformed it to obtain a single-gene overexpression strain. We found that overexpression of bchmgr, bcerg12, bcaba1, bcaba2, and bcaba3 genes increased the yield of 1',4'-trans-ABA-diol. The highest yielding ZX2 A3 strain was eventually screened, which produced a 1',4'-trans-ABA-diol concentration of 7.96 mg/g DCW (54.4 mg/L) in 144 h of shake flask fermentation. This represents a 2.1-fold increase compared to the ZX2 strain.
CONCLUSIONS
We utilized metabolic engineering techniques to alter the ABA-synthesizing strain B. cinerea, resulting in the creation of the mutant strain ZX2, which has the ability to produce 1',4'-trans-ABA-diol. By overexpressing the crucial genes involved in the 1',4'-trans-ABA-diol synthesis pathway in ZX2, we observed a substantial increase in the production of 1',4'-trans-ABA-diol.
Topics: Botrytis; Abscisic Acid; Fermentation; Metabolic Engineering; Fungal Proteins
PubMed: 38926702
DOI: 10.1186/s12934-024-02460-8 -
Scientific Reports Jun 2024Heterozygous de novo mutations in the Activity-Dependent Neuroprotective Homeobox (ADNP) gene underlie Helsmoortel-Van der Aa syndrome (HVDAS). Most of these mutations...
Heterozygous de novo mutations in the Activity-Dependent Neuroprotective Homeobox (ADNP) gene underlie Helsmoortel-Van der Aa syndrome (HVDAS). Most of these mutations are situated in the last exon and we previously demonstrated escape from nonsense-mediated decay by detecting mutant ADNP mRNA in patient blood. In this study, wild-type and ADNP mutants are investigated at the protein level and therefore optimal detection of the protein is required. Detection of ADNP by means of western blotting has been ambiguous with reported antibodies resulting in non-specific bands without unique ADNP signal. Validation of an N-terminal ADNP antibody (Aviva Systems) using a blocking peptide competition assay allowed to differentiate between specific and non-specific signals in different sample materials, resulting in a unique band signal around 150 kDa for ADNP, above its theoretical molecular weight of 124 kDa. Detection with different C-terminal antibodies confirmed the signals at an observed molecular weight of 150 kDa. Our antibody panel was subsequently tested by immunoblotting, comparing parental and homozygous CRISPR/Cas9 endonuclease-mediated Adnp knockout cell lines and showed disappearance of the 150 kDa signal, indicative for intact ADNP. By means of both a GFPSpark and Flag-tag N-terminally fused to a human ADNP expression vector, we detected wild-type ADNP together with mutant forms after introduction of patient mutations in E. coli expression systems by site-directed mutagenesis. Furthermore, we were also able to visualize endogenous ADNP with our C-terminal antibody panel in heterozygous cell lines carrying ADNP patient mutations, while the truncated ADNP mutants could only be detected with epitope-tag-specific antibodies, suggesting that addition of an epitope-tag possibly helps stabilizing the protein. However, western blotting of patient-derived hiPSCs, immortalized lymphoblastoid cell lines and post-mortem patient brain material failed to detect a native mutant ADNP protein. In addition, an N-terminal immunoprecipitation-competent ADNP antibody enriched truncating mutants in overexpression lysates, whereas implementation of the same method failed to enrich a possible native mutant protein in immortalized patient-derived lymphoblastoid cell lines. This study aims to shape awareness for critical assessment of mutant ADNP protein analysis in Helsmoortel-Van der Aa syndrome.
Topics: Humans; Homeodomain Proteins; Nerve Tissue Proteins; Mutation; HEK293 Cells; Autism Spectrum Disorder; Heart Diseases; Facies; Neurodevelopmental Disorders
PubMed: 38926592
DOI: 10.1038/s41598-024-65608-x -
Scientific Reports Jun 2024To analyse the genetic aetiology of a child with oculocutaneous albinism and to explore the effects of two mutation sites on the function of the OCA2 protein at the mRNA...
To analyse the genetic aetiology of a child with oculocutaneous albinism and to explore the effects of two mutation sites on the function of the OCA2 protein at the mRNA and protein levels via the use of recombinant carriers in vitro. Whole-exome sequencing (WES) and Sanger sequencing were used to analyse the pathogenic genes of the child and validate the mutations in the parents. pEGFP and phage vectors carrying wild-type and mutant OCA2 were constructed using the coding DNA sequence (CDS) of the whole gene-synthesized OCA2 as a template and transfected into HEK293T cells, after which expression analysis was performed. The child in this study was born with white skin, hair, eyelashes, and eyebrows and exhibited nystagmus. Genetic analysis indicated that the child carried two heterozygous mutations: c.1079C > T (p.Ser360Phe) of maternal origin and c.1095_1103delAGCACTGGC (p.Ala366_Ala368del) of paternal origin, conforming to an autosomal recessive inheritance pattern. In vitro analysis showed that the expression of the c.1079C > T (p.Ser360Phe) mutant did not significantly change at the mRNA level but did increase at the protein level, suggesting that the mutation may lead to enhanced protein stability, and the c.1095_1103delAGCACTGGC (p.Ala366_Ala368del) mutation resulted in the loss of three amino acids in exon 10, producing a truncated protein. In vitro expression analysis also revealed that the expression of the mutant gene was significantly downregulated at both the mRNA and protein levels, suggesting that the mutation can simultaneously produce truncated proteins and lead to protein degradation. This case study enriches the phenotypic spectrum of OCA2 gene disease. In vitro expression analysis confirmed that both mutations affect protein expression, providing a theoretical basis for analysing the pathogenicity of these two mutations.
Topics: Humans; HEK293 Cells; Mutation; Albinism, Oculocutaneous; Membrane Transport Proteins; Exome Sequencing; Female; Male; Pedigree; RNA, Messenger
PubMed: 38926510
DOI: 10.1038/s41598-024-64782-2 -
Nature Communications Jun 2024Anaerobic, acetogenic bacteria are well known for their ability to convert various one-carbon compounds, promising feedstocks for a future, sustainable biotechnology, to...
Anaerobic, acetogenic bacteria are well known for their ability to convert various one-carbon compounds, promising feedstocks for a future, sustainable biotechnology, to products such as acetate and biofuels. The model acetogen Acetobacterium woodii can grow on CO, formate or methanol, but not on carbon monoxide, an important industrial waste product. Since hydrogenases are targets of CO inhibition, here, we genetically delete the two [FeFe] hydrogenases HydA2 and HydBA in A. woodii. We show that the ∆hydBA/hydA2 mutant indeed grows on CO and produces acetate, but only after a long adaptation period. SNP analyzes of CO-adapted cells reveal a mutation in the HycB2 subunit of the HydA2/HydB2/HydB3/Fdh-containing hydrogen-dependent CO reductase (HDCR). We observe an increase in ferredoxin-dependent CO reduction and vice versa by the HDCR in the absence of the HydA2 module and speculate that this is caused by the mutation in HycB2. In addition, the CO-adapted ∆hydBA/hydA2 mutant growing on formate has a final biomass twice of that of the wild type.
Topics: Acetobacterium; Formates; Carbon Monoxide; Bacterial Proteins; Hydrogenase; Mutation; Carbon Dioxide; Electron Transport; Biomass; Acetates; Polymorphism, Single Nucleotide
PubMed: 38926344
DOI: 10.1038/s41467-024-49680-5 -
Cancer Medicine Jun 2024Members of the neurotrophic tropomyosin receptor kinase (NTRK) gene family, NTRK1, NTRK2, and NTRK3 encode TRK receptor tyrosine kinases. Intra- or inter-chromosomal...
BACKGROUND
Members of the neurotrophic tropomyosin receptor kinase (NTRK) gene family, NTRK1, NTRK2, and NTRK3 encode TRK receptor tyrosine kinases. Intra- or inter-chromosomal gene rearrangements produce NTRK gene fusions encoding fusion proteins which are oncogenic drivers in various solid tumors.
METHODS
This study investigated the prevalence of NTRK fusion genes and identified fusion partners in Japanese patients with solid tumors recorded in the Center for Cancer Genomics and Advanced Therapeutics database of comprehensive genomic profiling test.
RESULTS
In the analysis population (n = 46,621), NTRK fusion genes were detected in 91 patients (0.20%). The rate was higher in pediatric cases (<18 years; 1.69%) than in adults (0.16%). NTRK gene fusions were identified in 21 different solid tumor types involving 38 different partner genes including 22 (57.9%) previously unreported NTRK gene fusions. The highest frequency of NTRK gene fusions was head and neck cancer (1.31%) and thyroid cancer (1.31%), followed by soft tissue sarcoma (STS; 0.91%). A total of 97 NTRK fusion gene partners were analyzed involving mainly NTRK1 (49.5%) or NTRK3 (44.2%) gene fusions. The only fusion gene detected in head and neck cancer was ETV6::NTRK3 (n = 22); in STS, ETV6::NTRK3 (n = 7) and LMNA::NTRK1 (n = 5) were common. Statistically significant mutual exclusivity of NTRK fusions with alterations was confirmed in TP53, KRAS, and APC. NTRK gene fusion was detected from 11 STS cases: seven unclassified sarcoma, three sarcoma NOS, and one Ewing sarcoma.
CONCLUSIONS
NTRK gene fusion identification in solid tumors enables accurate diagnosis and potential TRK inhibitor therapy.
Topics: Humans; Japan; Oncogene Proteins, Fusion; Receptor, trkA; Male; Neoplasms; Female; Child; Adult; Receptor, trkC; Adolescent; Receptor, trkB; Prevalence; Young Adult; Middle Aged; Child, Preschool; Aged; Membrane Glycoproteins
PubMed: 38925616
DOI: 10.1002/cam4.7351 -
The Journal of Biological Chemistry Jun 2024The human AlkB homologs, ALKBH2 and ALKBH3, respond to methylation damage to maintain genomic integrity and cellular viability. Both ALKBH2 and ALKBH3 are direct...
The human AlkB homologs, ALKBH2 and ALKBH3, respond to methylation damage to maintain genomic integrity and cellular viability. Both ALKBH2 and ALKBH3 are direct reversal repair (DRR) enzymes that remove 1meA and 3meC lesions commonly generated by alkylating chemotherapeutic agents. Thus, the existence of deficiencies in ALKBH proteins can be exploited in synergy with chemotherapy. In this study, we investigated possible interactions between ALKBH2 and ALKBH3 with other proteins that could alter damage response and discovered an interaction with the mismatch repair (MMR) system. To test whether the lack of active MMR impacts ALKBH2 and/or ALKBH3 response to methylating agents, we generated cells deficient in ALKBH2, ALKBH3, or both in addition to Mlh homolog 1 (MLH1), another MMR protein. We found that MLH1ALKBH3 cells showed enhanced resistance towards S1- and S2-type methylating agents, whereas MLH1ALKBH2 cells were only resistant to S1-type methylating agents. Concomitant loss of ALKBH2 and ALKBH3 (ALKBH23) rendered cells sensitive to S1- and S2-agents, but the additional loss of MLH1 enhanced resistance to both types of damage. We also showed that ALKBH23 cells have an ATR-dependent arrest at the G/M checkpoint, increased apoptotic signalling, and replication fork stress in response to methylation. However, these responses were not observed with the loss of functional MLH1 in MLH1ALKBH23 cells. Finally, in MLH1ALKBH23 cells, we observed elevated mutant frequency in untreated and temozolomide treated cells. These results suggest that obtaining a more accurate prognosis of chemotherapeutic outcome requires information on the functionality of ALKBH2, ALKBH3, and MLH1.
PubMed: 38925328
DOI: 10.1016/j.jbc.2024.107492 -
ELife Jun 2024Cognitive decline is a significant health concern in our aging society. Here, we used the model organism to investigate the impact of the IIS/FOXO pathway on...
Cognitive decline is a significant health concern in our aging society. Here, we used the model organism to investigate the impact of the IIS/FOXO pathway on age-related cognitive decline. The Insulin/IGF-1 receptor mutant exhibits a significant extension of learning and memory span with age compared to wild-type worms, an effect that is dependent on the DAF-16 transcription factor. To identify possible mechanisms by which aging mutants maintain learning and memory with age while wild-type worms lose neuronal function, we carried out neuron-specific transcriptomic analysis in aged animals. We observed downregulation of neuronal genes and upregulation of transcriptional regulation genes in aging wild-type neurons. By contrast, IIS/FOXO pathway mutants exhibit distinct neuronal transcriptomic alterations in response to cognitive aging, including upregulation of stress response genes and downregulation of specific insulin signaling genes. We tested the roles of significantly transcriptionally-changed genes in regulating cognitive functions, identifying novel regulators of learning and memory. In addition to other mechanistic insights, a comparison of the aged vs young neuronal transcriptome revealed that a new set of potentially neuroprotective genes is upregulated; instead of simply mimicking a young state, may enhance neuronal resilience to accumulation of harm and take a more active approach to combat aging. These findings suggest a potential mechanism for regulating cognitive function with age and offer insights into novel therapeutic targets for age-related cognitive decline.
Topics: Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Forkhead Transcription Factors; Transcriptome; Neurons; Cognitive Aging; Aging; Receptor, Insulin; Signal Transduction; Gene Expression Regulation; Memory; Gene Expression Profiling
PubMed: 38922671
DOI: 10.7554/eLife.95621 -
Toxins May 2024produces fumonisins, which are mycotoxins inhibiting sphingolipid biosynthesis in humans, animals, and other eukaryotes. Fumonisins are presumed virulence factors of...
produces fumonisins, which are mycotoxins inhibiting sphingolipid biosynthesis in humans, animals, and other eukaryotes. Fumonisins are presumed virulence factors of plant pathogens, but may also play a role in interactions between competing fungi. We observed higher resistance to added fumonisin B (FB) in fumonisin-producing than in nonproducing , and likewise between isolates of and differing in production of sphinganine-analog toxins. It has been reported that in , ceramide synthase encoded in the fumonisin biosynthetic gene cluster is responsible for self-resistance. We reinvestigated the role of and by generating a double mutant strain in a background. Nearly unchanged resistance to added FB was observed compared to the parental strain. A recently developed fumonisin-sensitive baker's yeast strain allowed for the testing of candidate ceramide synthases by heterologous expression. The overexpression of the yeast gene, but not , increased fumonisin resistance. High-level resistance was conferred by , but not by . Likewise, strong resistance to FB was caused by overexpression of the presumed "housekeeping" ceramide synthases , , and , located outside the fumonisin cluster, indicating that possesses a redundant set of insensitive targets as a self-resistance mechanism.
Topics: Fumonisins; Fusarium; Oxidoreductases; Drug Resistance, Fungal; Fungal Proteins; Aspergillus; Alternaria
PubMed: 38922130
DOI: 10.3390/toxins16060235 -
ELife Jun 2024mutation is a driver mutation in the serrated pathway to colorectal cancers. BRAF drives tumorigenesis through constitutive downstream extracellular signal-regulated...
mutation is a driver mutation in the serrated pathway to colorectal cancers. BRAF drives tumorigenesis through constitutive downstream extracellular signal-regulated kinase (ERK) activation, but high-intensity ERK activation can also trigger tumor suppression. Whether and how oncogenic ERK signaling can be intrinsically adjusted to a 'just-right' level optimal for tumorigenesis remains undetermined. In this study, we found that FAK (Focal adhesion kinase) expression was reduced in -mutant adenomas/polyps in mice and patients. In ; mice, deletion maximized BRAF's oncogenic activity and increased cecal tumor incidence to 100%. Mechanistically, our results showed that Fak loss, without jeopardizing BRAF-induced ERK pathway transcriptional output, reduced EGFR (epidermal growth factor receptor)-dependent ERK phosphorylation. Reduction in ERK phosphorylation increased the level of Lgr4, promoting intestinal stemness and cecal tumor formation. Our findings show that a 'just-right' ERK signaling optimal for -induced cecal tumor formation can be achieved via Fak loss-mediated downregulation of ERK phosphorylation.
Topics: Animals; Proto-Oncogene Proteins B-raf; Phosphorylation; Mice; Humans; Cecal Neoplasms; Focal Adhesion Kinase 1; Extracellular Signal-Regulated MAP Kinases; MAP Kinase Signaling System; ErbB Receptors; Carcinogenesis; Receptors, G-Protein-Coupled; Male
PubMed: 38921956
DOI: 10.7554/eLife.94605