No Abstract Available.
Calmodulin* ; Cell Death* ; Humans* ; Retinoblastoma*

Species that belong to Penicillium section Sclerotiora are commonly found in various terrestrial environments, but only a few have been reported in marine environments. Because the number of Penicillium species reported in marine environments is increasing, we investigated the diversity of Penicillium section Sclerotiora in marine environments in Korea. Based on sequence analyses of β-tubulin and calmodulin loci, 21 strains of section Sclerotiora were identified as P. bilaiae, P. daejeonium, P. exsudans, P. herquei, P. cf. guanacastense, P. mallochii, P. maximae, and P. viticola. Three of them were confirmed as new to Korea: P. exsudans, P. mallochii, and P. maximae. Here, we have provided detailed morphological descriptions of these unrecorded species.
Calmodulin ; Korea ; Penicillium ; Phylogeny ; Sequence Analysis

Aspergillus (Trichocomaceae, Eurotiales, and Ascomycota) is a genus of well-defined asexual spore-forming fungi that produce valuable compounds such as secondary metabolites and enzymes; however, some species are also responsible for diseases in plants and animals, including humans. To date, 26 Aspergillus species have been reported in Korea, with most species located in terrestrial environments. In our study, Aspergillus species were isolated from mudflats and sea sand along the western and southern coasts of Korea. A total of 84 strains were isolated and identified as 17 Aspergillus species in 11 sections on the basis of both morphological characteristics and sequence analysis of the calmodulin gene (CaM) locus. Commonly isolated species were A. fumigatus (26 strains), A. sydowii (14 strains), and A. terreus (10 strains). The diversity of Aspergillus species isolated from mudflats (13 species) was higher than the diversity of those from sea sand (five species). Four identified species—A. caesiellus, A. montenegroi, A. rhizopodus, and A. tabacinus—are in the first records in Korea. Here, we provide detailed descriptions of the morphological characteristics of these four species.
Animals ; Aspergillus* ; Calmodulin ; Eurotiales ; Fungi ; Humans ; Korea* ; Phylogeny ; Sequence Analysis

Humans ; Calcium/metabolism* ; Calmodulin ; Arrhythmias, Cardiac ; Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism* ; Myocytes, Cardiac/metabolism* ; Phosphorylation

Tamoxifen, an antiestrogen, has previously been shown to induce apoptosis in HepG2 human hepatoblastoma cells through activation of the pathways independent of estrogen receptors, i.e., intracellular Ca2+ increase and generation of reactive oxygen species (ROS). However, the mechanism of tamoxifen to link increased intracellular Ca2+ to ROS generation is currently unknown. Thus, in this study we investigated the possible involvement of calmodulin, a Ca2+ activated protein, and Ca2+/ calmodulin-dependent protein kinase II in the above tamoxifen-induced events. Treatment with calmodulin antagonists (calmidazolium and trifluoroperazine) or specific inhibitors of Ca2+/calmodulin-dependent protein kinase II (KN-93 and KN-62) inhibited the tamoxifen-induced apoptosis in a dose-dependent manner. In addition, these agents blocked the tamoxifen-induced ROS generation in a concentration-dependent fashion, which was completely suppressed by intracellular Ca2+ chelation. These results demonstrate for the first time that, despite of its well-known direct calmodulin-inhibitory activity, tamoxifen may generate ROS and induce apoptosis through indirect activation of calmodulin and Ca2+/calmodulin-dependent protein kinase II in HepG2 cells.
Apoptosis* ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; Calmodulin* ; Carcinoma, Hepatocellular* ; Estrogen Receptor Modulators ; Hep G2 Cells ; Hepatoblastoma ; Humans* ; Protein Kinases ; Reactive Oxygen Species* ; Receptors, Estrogen ; Tamoxifen*

OBJECTIVETo investigate the role of heterogeneous expression of calcium handling proteins and spatial heterogeneity of APD restitution in the maintenance mechanism of ventricular fibrillation.

METHODSDuring programmed electrical simulation, APD restitution curves in the endocardium and epicardium of LV were constructed by plotting APD100 and diastolic interval. APD alternans, delayed after depolarization events were recorded simultaneously. Endocardial and epicardial myocytes were isolated from LV base and apex. Real time-PCR and Western blotting were performed to determine the relative messenger RNA and protein expression levels of calcium handling proteins.

RESULTSThe normal hearts have spatial heterogeneity of action potential restitution property and transmural heterogeneity of calcium handling proteins. The slopes of the APD restitution curve in the endocardium were significantly steeper than those in epicardium, and the slopes of APD curve at the LV apex were significantly steeper than those in LV base. However, delayed after depolarization events with larger amplitude and earlier onset consistently occurred in the endocardium of LV base. After programmed electrical simulation, the expression of messenger RNA of RyR2, SERCA2a except for Calstabin2 significantly decreased (by 57% and 41%, respectively, P < 0.05) in the endocardium of the base, while the expression of RyR2, SERCA2a, Calstabin2 significantly increased (by 90%, 78%and 64%, respectively, P < 0.05) in the epicardium of LV base. Although transmural heterogeneity of calcium handling proteins at the LV apex were also observed after rapid pacing, there is no significant differences in the transmural heterogeneity at the LV apex compared to the LV base. The base of LV has unique calcium handling properties.

CONCLUSIONSIt has been shown that Calcium cycling could modulate APD restitution property in the intact heart. The interaction between action potential and calcium dynamics instabilities is one of the most important reasons why simple criterion such as the APD restitution slope > 1 may fail to accurately predict the onset of APD alternans.

Action Potentials ; Animals ; Calcium ; metabolism ; Calmodulin ; metabolism ; Male ; Swine ; Ventricular Fibrillation ; metabolism ; physiopathology

Agarum clathratum, a brown macroalgae species, has recently become a serious environmental problem on the coasts of Korea. In an effort to solve this problem, fungal diversity associated with decaying A. clathratum was investigated and related β-glucosidase and endoglucanase activities were described. A total of 233 fungal strains were isolated from A. clathratum at 15 sites and identified 89 species based on morphology and a multigene analysis using the internal transcribed spacer region (ITS) and protein-coding genes including actin (act), β-tubulin (benA), calmodulin (CaM), and translation elongation factor (tef1). Acremonium, Corollospora, and Penicillium were the dominant genera, and Acremonium fuci and Corollospora gracilis were the dominant species. Fifty-one species exhibited cellulase activity, with A. fuci, Alfaria terrestris, Hypoxylon perforatum, P. madriti, and Pleosporales sp. Five showing the highest enzyme activities. Further enzyme quantification confirmed that these species had higher cellulase activity than P. crysogenum, a fungal species described in previous studies. This study lays the groundwork for bioremediation using fungi to remove decaying seaweed from populated areas and provides important background for potential industrial applications of environmentally friendly processes.
Acremonium ; Actins ; Biodegradation, Environmental ; Calmodulin ; Cellulase ; Fungi ; Korea ; Penicillium ; Peptide Elongation Factors ; Seaweed

Four strains of Penicillium and Talaromyces species are described and illustrated in an inventory of fungal species belonging to Eurotiales. The strains, CNUFC-DDS17-1, CNUFC-DDS27-1, CNUFC-PTM72-1, and CNUFC-YJW3-31, were isolated from soil and freshwater samples from South Korea. Based on their morphological characteristics and sequence analyses by the combined β-tubulin and calmodulin gene, the CNUFC-DDS17-1, CNUFC-DDS27-1, CNUFC-PTM72-1, and CNUFC-YJW3-31 isolates were identified as Penicillium pasqualense, Penicillium sanguifluum, Talaromyces apiculatus, and Talaromyces liani, respectively. The designated strains were found to represent a previously undescribed species of Korean fungal biota. In this study, detailed morphological descriptions and phylogenetic relationships of these species are provided.
Biota ; Calmodulin ; Eurotiales ; Fresh Water ; Korea ; Penicillium ; Sequence Analysis ; Soil ; Talaromyces

According to the data of Pinellia ternate transcriptome,two calmodulin genes were cloned and named as Pt Ca M1 and PtCa M2 respectively. The results of bioinformatics analysis showed that Pt Ca Ms genes contained a 450 bp open reading frame,encoding149 amino acids.The identity of the coding sequences was 80%,and the identity of amino acids sequence was 91%. Pt Ca Ms genes contained EF-hand structure domain,belonging to the Ca M families. The Real-time PCR analysed the expression patterns of Pt Ca Ms in different tissues and different treatments. RESULTS:: showed that Pt Ca M1 and Pt Ca M2 gene were the highest expression level in tuber. Under Ca Cl2 treatment,the expressions of Pt Ca Ms were significantly higher than the control. Under EGTA,La Cl3 and TFP treatments,the expression level of Pt Ca Ms decreased gradually. In this study,the Pt Ca Ms gene were successfully cloned from P. ternate,which laid a foundation for the functional characteristic of Pt Ca Ms gene and the synthesis of alkaloids from P. ternata for further study.
Calmodulin ; genetics ; Cloning, Molecular ; Genes, Plant ; Pinellia ; genetics ; Plant Tubers ; genetics

OBJECTIVE: To investigate the effect of calmodulin (CaM) and its mutants on binding to voltage-gated Na channel isoleucine-glutamine domain (Na1.2 IQ). METHODS: The cDNA of Na1.2 IQ was constructed by PCR technique, CaM mutants CaM, CaM and CaM were constructed with Quickchange site-directed mutagenesis kit (QIAGEN). The binding of Na1.2 IQ to CaM and CaM mutants under calcium and calcium free conditions were detected by pull-down assay. RESULTS: Na1.2 IQ and CaM were bound to each other at different calcium concentrations, while GST alone did not bind to CaM. The binding affinity of CaM and Na1.2 IQ at [Ca]-free was greater than that at 100 nmol/L [Ca] ( < 0.05). In the absence of calcium, the binding amount of CaM wild-type to Na1.2 IQ was greater than that of its mutant, and the binding affinity of CaM to Na1.2 IQ was the weakest among the three mutants ( < 0.05). CONCLUSIONS The binding ability of CaM and CaM mutants to Na1.2 IQ is Ca-dependent. This study has revealed a new mechanism of Na1.2 regulated by CaM, which would be useful for the study of ion channel related diseases.
Calcium ; metabolism ; Calmodulin ; genetics ; metabolism ; Mutation ; NAV1.2 Voltage-Gated Sodium Channel ; metabolism ; Protein Binding ; genetics