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1.
Sci Rep ; 14(1): 12826, 2024 06 04.
Article En | MEDLINE | ID: mdl-38834813

Lamin A/C gene (LMNA) mutations contribute to severe striated muscle laminopathies, affecting cardiac and skeletal muscles, with limited treatment options. In this study, we delve into the investigations of five distinct LMNA mutations, including three novel variants and two pathogenic variants identified in patients with muscular laminopathy. Our approach employs zebrafish models to comprehensively study these variants. Transgenic zebrafish expressing wild-type LMNA and each mutation undergo extensive morphological profiling, swimming behavior assessments, muscle endurance evaluations, heartbeat measurement, and histopathological analysis of skeletal muscles. Additionally, these models serve as platform for focused drug screening. We explore the transcriptomic landscape through qPCR and RNAseq to unveil altered gene expression profiles in muscle tissues. Larvae of LMNA(L35P), LMNA(E358K), and LMNA(R453W) transgenic fish exhibit reduced swim speed compared to LMNA(WT) measured by DanioVision. All LMNA transgenic adult fish exhibit reduced swim speed compared to LMNA(WT) in T-maze. Moreover, all LMNA transgenic adult fish, except LMNA(E358K), display weaker muscle endurance than LMNA(WT) measured by swimming tunnel. Histochemical staining reveals decreased fiber size in all LMNA mutations transgenic fish, excluding LMNA(WT) fish. Interestingly, LMNA(A539V) and LMNA(E358K) exhibited elevated heartbeats. We recognize potential limitations with transgene overexpression and conducted association calculations to explore its effects on zebrafish phenotypes. Our results suggest lamin A/C overexpression may not directly impact mutant phenotypes, such as impaired swim speed, increased heart rates, or decreased muscle fiber diameter. Utilizing LMNA zebrafish models for drug screening, we identify L-carnitine treatment rescuing muscle endurance in LMNA(L35P) and creatine treatment reversing muscle endurance in LMNA(R453W) zebrafish models. Creatine activates AMPK and mTOR pathways, improving muscle endurance and swim speed in LMNA(R453W) fish. Transcriptomic profiling reveals upstream regulators and affected genes contributing to motor dysfunction, cardiac anomalies, and ion flux dysregulation in LMNA mutant transgenic fish. These findings faithfully mimic clinical manifestations of muscular laminopathies, including dysmorphism, early mortality, decreased fiber size, and muscle dysfunction in zebrafish. Furthermore, our drug screening results suggest L-carnitine and creatine treatments as potential rescuers of muscle endurance in LMNA(L35P) and LMNA(R453W) zebrafish models. Our study offers valuable insights into the future development of potential treatments for LMNA-related muscular laminopathy.


Animals, Genetically Modified , Carnitine , Creatine , Lamin Type A , Muscle, Skeletal , Mutation , Zebrafish , Animals , Lamin Type A/genetics , Lamin Type A/metabolism , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Muscle, Skeletal/drug effects , Creatine/metabolism , Carnitine/metabolism , Disease Models, Animal , Laminopathies/genetics , Laminopathies/metabolism , Swimming , Transcriptome , Humans
2.
Hum Genomics ; 18(1): 55, 2024 May 31.
Article En | MEDLINE | ID: mdl-38822443

BACKGROUND: Although CDKN2A alteration has been explored as a favorable factor for tumorigenesis in pan-cancers, the association between CDKN2A point mutation (MUT) and intragenic deletion (DEL) and response to immune checkpoint inhibitors (ICIs) is still disputed. This study aims to determine the associations of CDKN2A MUT and DEL with overall survival (OS) and response to immune checkpoint inhibitors treatment (ICIs) among pan-cancers and the clinical features of CDKN2A-altered gastric cancer. METHODS: This study included 45,000 tumor patients that underwent tumor sequencing across 33 cancer types from four cohorts, the MSK-MetTropism, MSK-IMPACT, OrigiMed2020 and TCGA cohorts. Clinical outcomes and genomic factors associated with response to ICIs, including tumor mutational burden, copy number alteration, neoantigen load, microsatellite instability, tumor immune microenvironment and immune-related gene signatures, were collected in pan-cancer. Clinicopathologic features and outcomes were assessed in gastric cancer. Patients were grouped based on the presence of CDKN2A wild type (WT), CDKN2A MUT, CDKN2A DEL and CDKN2A other alteration (ALT). RESULTS: Our research showed that CDKN2A-MUT patients had shorter survival times than CDKN2A-WT patients in the MSK MetTropism and TCGA cohorts, but longer OS in the MSK-IMPACT cohort with ICIs treatment, particularly in patients having metastatic disease. Similar results were observed among pan-cancer patients with CDKN2A DEL and other ALT. Notably, CDKN2A ALT frequency was positively related to tumor-specific objective response rates to ICIs in MSK MetTropism and OrigiMed 2020. Additionally, individuals with esophageal carcinoma or stomach adenocarcinoma who had CDKN2A MUT had poorer OS than patients from the MSK-IMPACT group, but not those with adenocarcinoma. We also found reduced levels of activated NK cells, T cells CD8 and M2 macrophages in tumor tissue from CDKN2A-MUT or DEL pan-cancer patients compared to CDKN2A-WT patients in TCGA cohort. Gastric cancer scRNA-seq data also showed that CDKN2A-ALT cancer contained less CD8 T cells but more exhausted T cells than CDKN2A-WT cancer. A crucial finding of the pathway analysis was the inhibition of three immune-related pathways in the CDKN2A ALT gastric cancer patients, including the interferon alpha response, inflammatory response, and interferon gamma response. CONCLUSIONS: This study illustrates the CDKN2A MUT and DEL were associated with a poor outcome across cancers. CDKN2A ALT, on the other hand, have the potential to be used as a biomarker for choosing patients for ICI treatment, notably in esophageal carcinoma and stomach adenocarcinoma.


Cyclin-Dependent Kinase Inhibitor p16 , Stomach Neoplasms , Tumor Microenvironment , Humans , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Stomach Neoplasms/drug therapy , Stomach Neoplasms/immunology , Cyclin-Dependent Kinase Inhibitor p16/genetics , Tumor Microenvironment/genetics , Tumor Microenvironment/immunology , Male , Female , Immune Checkpoint Inhibitors/therapeutic use , Middle Aged , Biomarkers, Tumor/genetics , Aged , Prognosis , DNA Copy Number Variations/genetics , Mutation/genetics , Microsatellite Instability
3.
Am J Case Rep ; 25: e943466, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38822519

BACKGROUND Various resistance mechanisms of the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) have been reported, and approximately half of the cases show a T790M point mutation as resistance to EGFR-TKI. In addition, 3-14% of cases of non-small cell lung cancer transform into small cell lung carcinoma (SCLC) during treatment. However, there are few reported cases in which 2 mechanisms of resistance have been observed simultaneously. This report describes a 66-year-old man with initial presentation of stage IIA right-sided lung adenocarcinoma with EGFR gene exon 21 L858R mutation and 3 years of stable disease. During treatment with erlotinib, the patient developed SCLC and adenocarcinoma with EGFR exon 21 L858R and exon 20 T790M mutation. CASE REPORT A 66-year-old man underwent right pneumonectomy plus nodal dissection 2a for right hilar lung cancer and was diagnosed with an EGFR exon21 L858R mutated lung adenocarcinoma. Three years later, pleural dissemination was observed in the right chest wall. Although erlotinib was continued for 52 months, new metastases to the right ribs were detected. Chest wall tumor resection was performed. Based on the World Health Organization classification, the patient was diagnosed with combined SCLC, with EGFR exon21 L858R and exon20 T790M mutation. The patient received 4 cycles of carboplatin plus etoposide, 14 cycles of amrubicin, and 2 cycles of irinotecan. Chemotherapy continued for 25 months. CONCLUSIONS Long-term survival was achieved by chemotherapy after transformation. Since EGFR mutation-positive lung cancer shows a variety of acquired resistances, it is important to consider the treatment strategy of performing re-biopsy.


Adenocarcinoma of Lung , Adenocarcinoma , ErbB Receptors , Erlotinib Hydrochloride , Lung Neoplasms , Small Cell Lung Carcinoma , Aged , Humans , Male , Adenocarcinoma/drug therapy , Adenocarcinoma/genetics , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/genetics , Drug Resistance, Neoplasm , ErbB Receptors/genetics , Erlotinib Hydrochloride/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mutation , Small Cell Lung Carcinoma/genetics , Small Cell Lung Carcinoma/drug therapy , Small Cell Lung Carcinoma/pathology , /therapeutic use
5.
Rinsho Ketsueki ; 65(5): 362-374, 2024.
Article Ja | MEDLINE | ID: mdl-38825515

The epigenome regulates transcription of target genes through DNA methylation- or histone methylation/acetylation/phosphorylation/ubiquitination-mediated alteration of genomic function or chromatin conformation. Recent genomic studies have shown that multiple genes encoding epigenetic regulators are frequently and recurrently mutated in MDS, suggesting that epigenetic dysregulation is significantly associated with the molecular pathogenesis and clinical features of MDS. In this review, we will present our recent findings together with others, focusing on physiological molecular functions of epigenetic regulators recurrently mutated in MDS and on functional correlation between dysregulated epigenomic regulators and molecular pathogenesis/clinical features of MDS.


Epigenesis, Genetic , Myelodysplastic Syndromes , Humans , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/therapy , DNA Methylation , Mutation , Histones/metabolism
6.
Rinsho Ketsueki ; 65(5): 375-384, 2024.
Article Ja | MEDLINE | ID: mdl-38825516

Many novel agents have been developed for BCR::ABL1-negaive myeloproliferative neoplasms (MPN), namely, polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Some of these agents not only achieve hematologic complete response, reduce spleen size, and alleviate constitutional symptoms, but also induce molecular response, which means that they reduce the allele burden of driver gene mutations. These agents also prevent and alleviate fibrosis in bone marrow, which reduces the incidence of thrombotic events and disease progression and might improve prognosis. This article discusses the latest findings and promising treatments, including ongoing clinical trials, in PV, ET, and PMF.


Myeloproliferative Disorders , Humans , Myeloproliferative Disorders/genetics , Myeloproliferative Disorders/drug therapy , Myeloproliferative Disorders/therapy , Myeloproliferative Disorders/diagnosis , Mutation , Molecular Targeted Therapy
7.
Zhonghua Bing Li Xue Za Zhi ; 53(6): 578-584, 2024 Jun 08.
Article Zh | MEDLINE | ID: mdl-38825903

Objective: To correlate the common driver gene variations in primary lung adenocarcinoma with their clinical characteristics and histopathological subtypes. Methods: There were 4 995 cases of primary lung adenocarcinoma diagnosed at Weifang People's Hospital of Shandong Province from January 2015 to December 2021 which were retrospectively analyzed. Among them 1 983 cases were evaluated for their histopathological subtype; 3 012 were analyzed for the correlation of their histopathological subtypes and corresponding driver gene variations, including invasive non-mucinous adenocarcinoma (INMA) and invasive mucinous adenocarcinoma (IMA), and morphologically, poorly-differentiated, moderately-differentiated and well-differentiated adenocarcinomas. Next-generation sequencing was used to detect variations in EGFR, KRAS, ALK, RET, ROS1, MET, HER2, or BRAF driver genes. Results: There were 2 384 males and 2 611 females. EGFR and ALK variations were more commonly found in female patients aged 60 years or older, with EGFR mutation rate in clinical stage Ⅰ (25.80%) significantly higher than in other stages (P<0.05). KRAS mutations were more commonly detected in male smokers aged 60 years or older, HER2 mutations were more commonly in patients younger than 60 years, and RET mutations were more commonly in non-smokers (all P<0.05). No correlation was found between ROS1, MET, and BRAF gene variations and their clinical characteristics (P>0.05). For the histopathological subtypes, among the 1 899 cases of acinar adenocarcinoma, EGFR mutation rate was the highest (67.30%) compared to the other genes. Exon 21 L858R and exon 19 del were the main mutation sites in IMA and INMA, with a higher mutation rate at exon 20 T790M (11.63%) in micropapillary adenocarcinoma. In IMA, KRAS had the highest overall mutation rate (43.80%), with statistically significant difference in mutation rates of exon 2 G12D and exon 2 G12V in acinar adenocarcinoma, solid, and IMA (P<0.05). KRAS mutation at various sites were higher in poorly differentiated groups compared to moderately- and well-differentiated groups (P<0.05). HER2 mutations were more commonly observed in acinar adenocarcinoma, papillary, and micropapillary adenocarcinoma of INMA. BRAF mutation was higher in micropapillary adenocarcinoma compared with other types (P<0.05). Conclusions: Variations in EGFR, ALK, KRAS, HER2, and RET in primary lung adenocarcinoma are associated with patients' age, smoking history, and clinical stage, and driver gene mutations vary among different histopathological subtypes. EGFR mutations are predominant in INMA, while KRAS mutations are predominant in IMA.


Adenocarcinoma of Lung , Anaplastic Lymphoma Kinase , ErbB Receptors , Lung Neoplasms , Mutation , Proto-Oncogene Proteins B-raf , Proto-Oncogene Proteins p21(ras) , Receptor, ErbB-2 , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology , Female , Retrospective Studies , Anaplastic Lymphoma Kinase/genetics , ErbB Receptors/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Receptor, ErbB-2/genetics , Receptor, ErbB-2/metabolism , Protein-Tyrosine Kinases/genetics , Proto-Oncogene Proteins c-ret/genetics , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Proto-Oncogene Proteins/genetics , Adenocarcinoma, Mucinous/genetics , Adenocarcinoma, Mucinous/pathology , Middle Aged
8.
Zhonghua Bing Li Xue Za Zhi ; 53(6): 585-591, 2024 Jun 08.
Article Zh | MEDLINE | ID: mdl-38825904

Objective: To investigate the clinical, radiological, and pathological features of anaplastic gangliogliomas (AGGs) and to determine whether these tumors represent a distinct entity. Methods: Consecutive 667 cases of ganglioglioma (GG) diagnosed at the Xuanwu Hospital, Capital Medical University, Beijing, China between January 2015 and July 2023 were screened. Among these cases, 9 pathologically confirmed AGG cases were identified. Their clinical, radiological, treatment, and outcome data were analyzed retrospectively. Most of the tumor samples were subject to next-generation sequencing, while a subset of them were subject to DNA methylation profiling. Results: Among the 9 patients, there were five males and four females, with a median age of 8 years. Epileptic seizures (5/9) were the most frequently presented symptom. Radiological examinations showed three types of radiological manifestations: four cases showed abnormal MRI signals with no significant mass effects and mild enhancement; two cases demonstrated a mixed solid-cystic density lesion with peritumoral edema, which showed significant heterogeneous enhancement and obvious mass effects, and one case displayed cystic cavity formation with nodules on MRI, which showed evident enhancements. All cases exhibited mutations that were predicted to activate the MAP kinase signaling pathway, including seven with BRAF p.V600E mutation and two with NF1 mutation. Five AGGs with mutations involving the MAP kinase signaling pathway also had concurrent mutations, including three with CDKN2A homozygous deletion, one with a TERT promoter mutation, one with a H3F3A mutation, and one with a PTEN mutation. Conclusions: AGG exhibits a distinct spectrum of pathology, genetic mutations and clinical behaviors, differing from GG. Given these characteristics suggest that AGG may be a distinct tumor type, further expansion of the case series is needed. Therefore, a comprehensive integration of clinical, histological, and molecular analyses is required to correctly diagnose AGG. It will also help guide treatments and prognostication.


Brain Neoplasms , DNA Methylation , Ganglioglioma , Magnetic Resonance Imaging , Mutation , PTEN Phosphohydrolase , Proto-Oncogene Proteins B-raf , Humans , Ganglioglioma/pathology , Ganglioglioma/genetics , Male , Female , Child , Retrospective Studies , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Brain Neoplasms/diagnostic imaging , Proto-Oncogene Proteins B-raf/genetics , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Telomerase/genetics , Histones/genetics , Histones/metabolism , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Epilepsy/pathology , Epilepsy/genetics
10.
Physiol Plant ; 176(3): e14369, 2024.
Article En | MEDLINE | ID: mdl-38828612

High temperature (HT) affects the production of chlorophyll (Chl) pigment and inhibits cellular processes that impair photosynthesis, and growth and development in plants. However, the molecular mechanisms underlying heat stress in rice are not fully understood yet. In this study, we identified two mutants varying in leaf color from the ethylmethanesulfonate mutant library of indica rice cv. Zhongjiazao-17, which showed pale-green leaf color and variegated leaf phenotype under HT conditions. Mut-map revealed that both mutants were allelic, and their phenotype was controlled by a single recessive gene PALE GREEN LEAF 10 (PGL10) that encodes NADPH:protochlorophyllide oxidoreductase B, which is required for the reduction of protochlorophyllide into chlorophyllide in light-dependent tetrapyrrole biosynthetic pathway-based Chl synthesis. Overexpression-based complementation and CRISPR/Cas9-based knockout analyses confirmed the results of Mut-map. Moreover, qRT-PCR-based expression analysis of PGL10 showed that it expresses in almost all plant parts with the lowest expression in root, followed by seed, third leaf, and then other green tissues in both mutants, pgl10a and pgl10b. Its protein localizes in chloroplasts, and the first 17 amino acids from N-terminus are responsible for signals in chloroplasts. Moreover, transcriptome analysis performed under HT conditions revealed that the genes involved in the Chl biosynthesis and degradation, photosynthesis, and reactive oxygen species detoxification were differentially expressed in mutants compared to WT. Thus, these results indicate that PGL10 is required for maintaining chloroplast function and plays an important role in rice adaptation to HT stress conditions by controlling photosynthetic activity.


Oryza , Photosynthesis , Plant Proteins , Oryza/genetics , Oryza/physiology , Oryza/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant , Chloroplasts/metabolism , Hot Temperature , Plant Leaves/genetics , Plant Leaves/metabolism , Plant Leaves/physiology , Chlorophyll/metabolism , Mutation , Heat-Shock Response/genetics , Loss of Function Mutation , Phenotype , Oxidoreductases Acting on CH-CH Group Donors
11.
Ideggyogy Sz ; 77(5-6): 207-211, 2024 May 30.
Article Hu | MEDLINE | ID: mdl-38829246

Background - Leukodystrophies, a hete­ro­­ge­neous group of brain and spinal cord dis­orders, often pose challenges in es­tab­li­shing molecular etiology. Vanishing White Matter Disease (VWMD) is a rare sub­type of leu­ko­dys­trophies presenting with characteristic clinical and MRI features, ne­ver­theless, achieving diag­nostic certainty requires genetic studies.

Case presentation - Our patient is a nine year old girl, who developed progressive gait difficulties at around 3-4 years of age. Her brain MRI showed confluent lesions with in­­creased signal intensity in the cerebral and cerebellar white matter on T2/FLAIR se­quen­ces, within which hypointense regions ap­peared with signal intensity resembling that of the cerebrospinal fluid on T1 sequences. Whole exome sequencing identified a homozygous likely pathogenic variant within the EIF2B5 gene in the proband, which was present in a heterozygous state in both asymptomatic parents. Having the clinical and molecular genetic diagnosis established, we explored therapeutic possibilities for the patient.

Conclusion - VWMD is a severe form of leukodystrophies with little or no disease modifying therapy available until recently. A better understanding of its molecular pathogenesis offers some hope for new inventive therapies. 

.


Eukaryotic Initiation Factor-2B , Leukoencephalopathies , Mutation , Humans , Leukoencephalopathies/genetics , Leukoencephalopathies/diagnostic imaging , Leukoencephalopathies/pathology , Female , Eukaryotic Initiation Factor-2B/genetics , Child , Magnetic Resonance Imaging , White Matter/diagnostic imaging , White Matter/pathology
12.
World J Microbiol Biotechnol ; 40(7): 230, 2024 Jun 03.
Article En | MEDLINE | ID: mdl-38829459

ß-Carotene is an attractive compound and that its biotechnological production can be achieved by using engineered Saccharomyces cerevisiae. In a previous study, we developed a technique for the efficient establishment of diverse mutants through the introduction of point and structural mutations into the yeast genome. In this study, we aimed to improve ß-carotene production by applying this mutagenesis technique to S. cerevisiae strain that had been genetically engineered for ß-carotene production. Point and structural mutations were introduced into ß-carotene-producing engineered yeast. The resulting mutants showed higher ß-carotene production capacity than the parental strain. The top-performing mutant, HP100_74, produced 37.6 mg/L of ß-carotene, a value 1.9 times higher than that of the parental strain (20.1 mg/L). Gene expression analysis confirmed an increased expression of multiple genes in the glycolysis, mevalonate, and ß-carotene synthesis pathways. In contrast, expression of ERG9, which functions in the ergosterol pathway competing with ß-carotene production, was decreased in the mutant strain. The introduction of point and structural mutations represents a simple yet effective method for achieving mutagenesis in yeasts. This technique is expected to be widely applied in the future to produce chemicals via metabolic engineering of S. cerevisiae.


Metabolic Engineering , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , beta Carotene , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , beta Carotene/biosynthesis , beta Carotene/metabolism , Metabolic Engineering/methods , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Mutation , Gene Expression Regulation, Fungal , Carotenoids/metabolism , Mutagenesis , Point Mutation , Mevalonic Acid/metabolism , Biosynthetic Pathways/genetics , Farnesyl-Diphosphate Farnesyltransferase
13.
Mol Biol Rep ; 51(1): 706, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38824203

BACKGROUND: Microinjection is a direct procedure for delivering various compounds via micropipette into individual cells. Combined with the CRISPR/Cas9 editing technology, it has been used to produce genetically engineered animal cells. However, genetic micromanipulation of intact plant cells has been a relatively unexplored area of research, partly due to the cytological characteristics of these cells. This study aimed to gain insight into the genetic micromanipulation of wheat microspores using microinjection procedures combined with the CRISPR/Cas9 editing system targeting the Ms2 gene. METHODS AND RESULTS: Microspores were first reprogrammed by starvation and heat shock treatment to make them structurally suitable for microinjection. The large central vacuole was fragmented and the nucleus with cytoplasm was positioned in the center of the cell. This step and an additional maltose gradient provided an adequate source of intact single cells in the three wheat genotypes. The microcapillary was inserted into the cell through the germ pore to deliver a working solution with a fluorescent marker. This procedure was much more efficient and less harmful to the microspore than inserting the microcapillary through the cell wall. The CRISPR/Cas9 binary vectors injected into reprogrammed microspores induced mutations in the target Ms2 gene with deletions ranging from 1 to 16 bp. CONCLUSIONS: This is the first report of successful genome editing in an intact microspore/wheat cell using the microinjection technique and the CRISPR/Cas9 editing system. The study presented offers a range of molecular and cellular biology tools that can aid in genetic micromanipulation and single-cell analysis.


CRISPR-Cas Systems , Gene Editing , Microinjections , Mutation , Triticum , Triticum/genetics , CRISPR-Cas Systems/genetics , Gene Editing/methods , Microinjections/methods , Mutation/genetics , Pollen/genetics
14.
Mol Biol Rep ; 51(1): 714, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38824264

BACKGROUND: NOTCH3 variants are known to be linked to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). However, some null NOTCH3 variants with homozygous inheritance cause neurological symptoms distinct from CADASIL. The aim of this study was to expand the clinical spectrum of this distinct condition and provide further evidence of its autosomal recessive inheritance. METHODS AND RESULTS: Whole exome sequencing (WES) was performed on a proband who exhibited livedo racemosa, ataxia, cognitive decline, seizures, and MRI white matter abnormalities without anterior temporal pole lesions. Segregation analysis was conducted with Sanger sequencing. WES of the proband identified a novel homozygous NOTCH3 null variant (c.2984delC). The consanguineous parents were confirmed as heterozygous variant carriers. In addition, three heterozygous NOTCH3 null variants were reported as incidental findings in three unrelated cases analyzed in our center. CONCLUSION: The findings of this study suggest an autosomal recessive inheritance pattern in this early-onset leukoencephalopathy, in contrast to CADASIL's dominant gain-of-function mechanism; which is a clear example of genotype-phenotype correlation. Comprehensive genetic analysis provides valuable insights into disease mechanisms and facilitates diagnosis and family planning for NOTCH3-associated neurological disorders.


Exome Sequencing , Genes, Recessive , Pedigree , Phenotype , Receptor, Notch3 , Humans , Receptor, Notch3/genetics , Male , Female , Exome Sequencing/methods , Genes, Recessive/genetics , Adult , Genetic Association Studies , CADASIL/genetics , Magnetic Resonance Imaging/methods , Alleles , Homozygote , Consanguinity , Loss of Function Mutation/genetics , Mutation/genetics , Heterozygote
15.
Environ Microbiol Rep ; 16(3): e13269, 2024 Jun.
Article En | MEDLINE | ID: mdl-38822640

Recombinational repair is an important mechanism that allows DNA replication to overcome damaged templates, so the DNA is duplicated timely and correctly. The RecFOR pathway is one of the common ways to load RecA, while the RuvABC complex operates in the resolution of DNA intermediates. We have generated deletions of recO, recR and ruvB genes in Thermus thermophilus, while a recF null mutant could not be obtained. The recO deletion was in all cases accompanied by spontaneous loss of function mutations in addA or addB genes, which encode a helicase-exonuclease also key for recombination. The mutants were moderately affected in viability and chromosome segregation. When we generated these mutations in a Δppol/addAB strain, we observed that the transformation efficiency was maintained at the typical level of Δppol/addAB, which is 100-fold higher than that of the wild type. Most mutants showed increased filamentation phenotypes, especially ruvB, which also had DNA repair defects. These results suggest that in T. thermophilus (i) the components of the RecFOR pathway have differential roles, (ii) there is an epistatic relationship of the AddAB complex over the RecFOR pathway and (iii) that neither of the two pathways or their combination is strictly required for viability although they are necessary for normal DNA repair and chromosome segregation.


Bacterial Proteins , DNA Helicases , Thermus thermophilus , Thermus thermophilus/genetics , Thermus thermophilus/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , DNA Helicases/genetics , DNA Helicases/metabolism , DNA Repair/genetics , Gene Deletion , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Chromosome Segregation/genetics , DNA, Bacterial/genetics , Mutation
17.
World J Microbiol Biotechnol ; 40(7): 228, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38822927

Doramectin, an essential animal anthelmintic, is synthesized through the fermentation process of Streptomyces avermitilis. This study delves into the transcriptomic profiles of two strains, namely the doramectin-producing wild-type S. avermitilis N72 and its highly doramectin-producing mutant counterpart, S. avermitilis XY-62. Comparative analysis revealed 860 up-regulated genes and 762 down-regulated genes in the mutant strain, notably impacting the expression of key genes pivotal in doramectin biosynthesis, including aveA1, aveA2, aveA3, aveA4, aveE, and aveBI. These findings shed light on the molecular mechanisms underpinning the heightened doramectin production in S. avermitilis XY-62, presenting promising avenues for optimizing doramectin production processes.


Gene Expression Profiling , Gene Expression Regulation, Bacterial , Ivermectin , Mutation , Streptomyces , Transcriptome , Streptomyces/genetics , Streptomyces/metabolism , Ivermectin/analogs & derivatives , Ivermectin/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Fermentation , Anthelmintics/metabolism
18.
Int Heart J ; 65(3): 580-585, 2024.
Article En | MEDLINE | ID: mdl-38825499

Cardiac ryanodine receptor (RyR2) gain-of-function mutations cause catecholaminergic polymorphic ventricular tachycardia (CPVT). Conversely, RyR2 loss-of-function mutations cause a new disease entity, termed calcium release deficiency syndrome (CRDS), which may include RYR2-related long QT syndrome (LQTS). Importantly, unlike CPVT, patients with CRDS do not always exhibit exercise- or epinephrine-induced ventricular arrhythmias, which precludes a diagnosis of CRDS. Here we report a boy and his father, who both experienced exercise-induced cardiac events and harbor the same RYR2 E4107A variant. In the boy, an exercise stress test (EST) and epinephrine provocation test (EPT) did not induce any ventricular arrhythmias. QTc was slightly prolonged (QTc: 474 ms), and an EPT induced QTc prolongation (QTc-baseline: 466 ms, peak: 532 ms, steady-state: 527 ms). In contrast, in his father, QTc was not prolonged (QTc: 417 ms), and neither an EST nor EPT induced QTc prolongation. However, an EST induced multifocal premature ventricular contraction (PVC) bigeminy and bidirectional PVC couplets. Thus, they exhibited distinct clinical phenotypes: the boy exhibited LQTS (or CRDS) phenotype, whereas his father exhibited CPVT phenotype. These findings suggest that, in addition to the altered RyR2 function, other unidentified factors, such as other genetic, epigenetic, and environmental factors, and aging, may be involved in the diverse phenotypic manifestations. Considering that a single RYR2 variant can cause both CPVT and LQTS (or CRDS) phenotypes, in cascade screening of patients with CPVT and CRDS, an EST and EPT are not sufficient and genetic analysis is required to identify individuals who are at increased risk for life-threatening arrhythmias.


Long QT Syndrome , Phenotype , Ryanodine Receptor Calcium Release Channel , Tachycardia, Ventricular , Humans , Ryanodine Receptor Calcium Release Channel/genetics , Male , Long QT Syndrome/genetics , Long QT Syndrome/diagnosis , Tachycardia, Ventricular/genetics , Tachycardia, Ventricular/diagnosis , Electrocardiography , Pedigree , Adult , Exercise Test , Mutation
19.
Rinsho Ketsueki ; 65(5): 343-352, 2024.
Article Ja | MEDLINE | ID: mdl-38825513

The blood cancer field has played a pioneering role in advancing precision medicine, with milestones such as development of ABL1 inhibitors for chronic myeloid leukemia. The significance of gene mutation information in AML treatment has increased, evident in classifications and guidelines from organizations such as WHO and ELN. This article examines the anticipated roles of cancer genome panels (CGPs) in AML treatment from three perspectives: diagnosis, risk stratification, and treatment selection. Use of CGPs enables more accurate diagnosis and risk stratification. In treatment selection, CGPs not only complements but also substitutes existing companion diagnostics, and is expected to be a crucial information source for future drug adoption and investigation of tumor-agnostic therapies. However, various challenges remain to be addressed, including the purpose and timing of CGPs, the time required for the tests, and how to utilize expert panels.


Leukemia, Myeloid, Acute , Humans , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/diagnosis , Mutation , Genome, Human , Precision Medicine
20.
Open Biol ; 14(6): 240041, 2024 Jun.
Article En | MEDLINE | ID: mdl-38835242

Platelets are blood cells derived from megakaryocytes that play a central role in regulating haemostasis and vascular integrity. The microtubule cytoskeleton of megakaryocytes undergoes a critical dynamic reorganization during cycles of endomitosis and platelet biogenesis. Quiescent platelets have a discoid shape maintained by a marginal band composed of microtubule bundles, which undergoes remarkable remodelling during platelet activation, driving shape change and platelet function. Disrupting or enhancing this process can cause platelet dysfunction such as bleeding disorders or thrombosis. However, little is known about the molecular mechanisms underlying the reorganization of the cytoskeleton in the platelet lineage. Recent studies indicate that the emergence of a unique platelet tubulin code and specific pathogenic tubulin mutations cause platelet defects and bleeding disorders. Frequently, these mutations exhibit dominant negative effects, offering valuable insights into both platelet disease mechanisms and the functioning of tubulins. This review will highlight our current understanding of the role of the microtubule cytoskeleton in the life and death of platelets, along with its relevance to platelet disorders.


Blood Platelets , Cytoskeleton , Megakaryocytes , Microtubules , Humans , Blood Platelets/metabolism , Megakaryocytes/metabolism , Megakaryocytes/cytology , Cytoskeleton/metabolism , Microtubules/metabolism , Tubulin/metabolism , Tubulin/genetics , Animals , Blood Platelet Disorders/metabolism , Blood Platelet Disorders/genetics , Blood Platelet Disorders/pathology , Mutation
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