Chlamydomonas DYX1C1/PF23 is essential for axonemal assembly and proper morphology of inner dynein arms

Cytoplasmic assembly of ciliary dyneins, a process known as preassembly, requires numerous non-dynein proteins, but the identities and functions of these proteins are not fully elucidated. Here, we show that the classical Chlamydomonas motility mutant pf23 is defective in the Chlamydomonas homolog of DYX1C1. The pf23 mutant has a 494 bp deletion in the DYX1C1 gene and expresses a shorter DYX1C1 protein in the cytoplasm. Structural analyses, using cryo-ET, reveal that pf23 axonemes lack most of the inner dynein arms. Spectral counting confirms that DYX1C1 is essential for the assembly of the majority of ciliary inner dynein arms (IDA) as well as a fraction of the outer dynein arms (ODA). A C-terminal truncation of DYX1C1 shows a reduction in a subset of these ciliary IDAs. Sucrose gradients of cytoplasmic extracts show that preassembled ciliary dyneins are reduced compared to wild-type, which suggests an important role in dynein complex stability. The role of PF23/DYX1C1 remains unknown, but we suggest that DYX1C1 could provide a scaffold for macromolecular assembly

Microarray-Based Transcriptional Profiling of Renieramycin M and Jorunnamycin C, Isolated from Thai Marine Organisms

Renieramycin M and jorunnamycin C, two isoquinolinequinone compounds differing only at the C-22 ester side chain, were evaluated for their cytotoxic effects on human colon (HCT116) and breast (MDA-MB-435) cancer cell lines. These two compounds displayed potent cancer cell growth inhibition, their IC50 values reaching nanomolar order. To examine their effects on transcription, we carried out oligonucleotide microarray analysis with focus on the similarities and differences between the two compounds in terms of transcriptional profiles. We found that the down-regulation of PTPRK (protein tyrosine phosphatase receptor type K) can be considered as a biomarker responsive to the cytotoxic effects of this class of antitumor marine natural products

Transient left ventricular apical ballooning without coronary artery stenosis: a novel heart syndrome mimicking acute myocardial infarction

AbstractOBJECTIVESTo determine the clinical features of a novel heart syndrome with transient left ventricular (LV) apical ballooning, but without coronary artery stenosis, that mimics acute myocardial infarction, we performed a multicenter retrospective enrollment study.BACKGROUNDOnly several case presentations have been reported with regard to this syndrome.METHODSWe analyzed 88 patients (12 men and 76 women), aged 67 ± 13 years, who fulfilled the following criteria: 1) transient LV apical ballooning, 2) no significant angiographic stenosis, and 3) no known cardiomyopathies.RESULTSThirty-eight (43%) patients had preceding aggravation of underlying disorders (cerebrovascular accident [n = 3], epilepsy [n = 3], exacerbated bronchial asthma [n = 3], acute abdomen [n = 7]) and noncardiac surgery or medical procedure (n = 11) at the onset. Twenty-four (27%) patients had emotional and physical problems (sudden accident [n = 2], death/funeral of a family member [n = 7], inexperience with exercise [n = 6], quarreling or excessive alcohol consumption [n = 5] and vigorous excitation [n = 4]). Chest symptoms (67%), electrocardiographic changes (ST elevation [90%], Q-wave formation [27%] and T-wave inversion [97%]) and elevated creatine kinase (56%) were found. After treatment of pulmonary edema (22%), cardiogenic shock (15%) and ventricular tachycardia/fibrillation (9%), 85 patients had class I New York Heart Association function on discharge. The LV ejection fraction improved from 41 ± 11% to 64 ± 10%. Transient intraventricular pressure gradient and provocative vasospasm were documented in 13/72 (18%) and 10/48 (21%) of the patients, respectively. During follow-up for 13 ± 14 months, two patients showed recurrence, and one died suddenly.CONCLUSIONSA novel cardiomyopathy with transient apical ballooning was reported. Emotional or physical stress might play a key role in this cardiomyopathy, but the precise etiologic basis still remains unclear

Chlamydomonas DYX1C1/PF23 is essential for axonemal assembly and proper morphology of inner dynein arms

Cytoplasmic assembly of ciliary dyneins, a process known as preassembly, requires numerous non-dynein proteins, but the identities and functions of these proteins are not fully elucidated. Here, we show that the classical Chlamydomonas motility mutant pf23 is defective in the Chlamydomonas homolog of DYX1C1. The pf23 mutant has a 494 bp deletion in the DYX1C1 gene and expresses a shorter DYX1C1 protein in the cytoplasm. Structural analyses, using cryo-ET, reveal that pf23 axonemes lack most of the inner dynein arms. Spectral counting confirms that DYX1C1 is essential for the assembly of the majority of ciliary inner dynein arms (IDA) as well as a fraction of the outer dynein arms (ODA). A C-terminal truncation of DYX1C1 shows a reduction in a subset of these ciliary IDAs. Sucrose gradients of cytoplasmic extracts show that preassembled ciliary dyneins are reduced compared to wild-type, which suggests an important role in dynein complex stability. The role of PF23/DYX1C1 remains unknown, but we suggest that DYX1C1 could provide a scaffold for macromolecular assembly

Antitumor activity- and gene expression-based profiling of ecteinascidin Et 743 and phthalascidin Pt 650

AbstractBackground: Ecteinascidin 743 (Et 743) is a potent antitumor marine alkaloid currently undergoing phase II clinical trials. The synthetic analog phthalascidin (Pt 650), a designed structural analog of Et 743 displays in vitro potency comparable to Et 743. In this study, we used a panel of 36 human cancer cell lines, flow cytometry and oligonucleotide microarrays to analyze further these two compounds in a parallel fashion with regard to both antitumor activity (phenotype) and gene expression (genotype) bases.Results: The cancer panel experiment established that activity patterns of Et 743 and Pt 650 were essentially the same with their IC50 values ranging from pM to low nM. By means of flow cytometric cell cycle analysis using HCT116 cells, they were shown to disrupt S phase progression after a 12-h treatment at 2.0 nM, eventually resulting in the late S and G2/M accumulation at the 24-h time point. Array-based gene expression monitoring also demonstrated that the Et 743 and Pt 650 profiles were highly similar in two distinct cancer cell lines, HCT116 colon and MDA-MB-435 breast. Characteristic changes were observed in subsets of genes involved in DNA damage response, transcription and signal transduction. In HCT116 carrying the wild-type p53 tumor suppressor gene, the up-regulation of several p53-responsive genes was evident. Furthermore, a subset of genes encoding DNA-binding proteins to specific promoter regions (e.g. the CCAAT box) was down-regulated in both cell lines, suggesting one potential mode of action of this series of antitumor agents.Conclusion: A combination of gene expression analysis using oligonucleotide microarrays and flow cytometry confirms an earlier finding that Et 743 and Pt 650 have remarkably similar biological activities

Sulfonamide Drugs Binding to the Colchicine Site of Tubulin: Thermodynamic Analysis of the Drug-Tubulin Interactions by Isothermal Titration Calorimetry

The discovery of several sulfonamide drugs paved the way toward thesynthesis of 6(N-12-[(4-hydroxyphenyl)amino]-3-pyridinyl]-4-methoxybenzenesulfonamide:E7010) and 7(N-(3fluoro-4-methoxyphenyl)pentafluorobenzenesulfonamide, T138067),both of which inhibit, tubulin polymerization and are under clinicaldevelopment. A series of diarylsulforiamides containing an indolescaffold was also found to have antimitotic properties, but, their modeof interactions with tubulin has remained unidentified so far. In thisstudy: we demonstrate that these sulfonamide drugs bind to thecolchicine site of tubulin in a reversible manner. They quenchedintrinsic tryptophan fluorescence of tubulin presumably due todrug-induced conformational changes in the protein, but were unable tomodulate GTPase activity of tubulin in contrast to colchicine thatenhances the same enzymatic activity. Further investigation usingisothermal titration calorimetry (ITC) revealed that 5(N-(5-chloro-7-indolyl)-4-methoxybenzenesulfonamide) afforded a largepositive value of heat capacity change (\Delta C_p) = +264, cal mol^-^1 K^-^1) on binding to tubulin, suggesting a substantial conformationaltransition in the protein along with partial enthalpy- entropycompensation. On the other hand. the 2-chloro regioisomer 2 gave alarge negative value of \Delta C_p(-589 cal mol^-^1 K^-^1) along withcomplete enthalpyentropy compensation. This thermodynamic profile wasthought to be attributable to a prominent contribution of van der Waalsinteraction and hydrogen bonding between Specific groups in thedrug-tubulin complex. These results indicate that a mere alteration inthe position of a single substituent chlorine on the indole scaffoldhas a great influence on the drug-tublin binding thermodynamics

Social Co-OS: Cyber-Human Social Co-Operating System

The novel concept of a Cyber-Human Social System (CHSS) and a diverse and pluralistic 'mixed-life society' is proposed, wherein cyber and human societies commit to each other. This concept enhances the Cyber-Physical System (CPS), which is associated with the current Society 5.0, a social vision realised through the fusion of cyber (virtual) and physical (real) spaces following information society (Society 4.0 and Industry 4.0). Moreover, the CHSS enhances the Human-CPS, the Human-in-the-Loop CPS (HiLCPS), and the Cyber-Human System by intervening in individual behaviour pro-socially and supporting consensus building. As a form of architecture that embodies the CHSS concept, the Cyber-Human Social Co-Operating System (Social Co-OS) that combines cyber and human societies is shown. In this architecture, the cyber and human systems cooperate through the fast loop (operation and administration) and slow loop (consensus and politics). Furthermore, the technical content and current implementation of the basic functions of the Social Co-OS are described. These functions consist of individual behavioural diagnostics, interventions in the fast loop, group decision diagnostics and consensus building in the slow loop. Subsequently, this system will contribute to mutual aid communities and platform cooperatives.Comment: 14 pages, 14 figures. see https://ietresearch.onlinelibrary.wiley.com/doi/10.1049/cps2.1203