Molecular cloning and expression profile of Xenopus calcineurin A subunit11The nucleotide sequence of XCnA has been deposited in DDBJ/DMBL/GenBank DNA database under the accession number AB037146.

AbstractWe have cloned a cDNA encoding a catalytic subunit of calcineurin (CnA) expressed in Xenopus oocytes. The deduced amino acid sequence indicates 96.3% and 96.8% identities with the mouse and human CnAα isoforms, respectively. Xenopus CnA (XCnA) RNA and protein are expressed as maternal and throughout development. Recombinant XCnA protein interacted with calmodulin in the presence of Ca2+. Deletion of calmodulin binding domain and auto-inhibitory domain revealed calcium independent phosphatase activity, thereby showing that XCnA is likely to be modulated by both calmodulin and calcium

Zic2 and Zic3 synergistically control neurulation and segmentation of paraxial mesoderm in mouse embryo

AbstractZic family zinc-finger proteins play various roles in animal development. In mice, five Zic genes (Zic1–5) have been reported. Despite the partly overlapping expression profiles of these genes, mouse mutants for each Zic show distinct phenotypes. To uncover possible redundant roles, we characterized Zic2/Zic3 compound mutant mice. Zic2 and Zic3 are both expressed in presomitic mesoderm, forming and newly generated somites with differential spatiotemporal accentuation. Mice heterozygous for the hypomorphic Zic2 allele together with null Zic3 allele generally showed severe malformations of the axial skeleton, including asymmetric or rostro-caudally bridged vertebrae, and reduction of the number of caudal vertebral bones, that are not obvious in single mutants. These defects were preceded by perturbed somitic marker expression, and reduced paraxial mesoderm progenitors in the primitive streak. These results suggest that Zic2 and Zic3 cooperatively control the segmentation of paraxial mesoderm at multiple stages. In addition to the segmentation abnormality, the compound mutant also showed neural tube defects that ran the entire rostro-caudal extent (craniorachischisis), suggesting that neurulation is another developmental process where Zic2 and Zic3 have redundant functions

Clinical effects of stereotactic radiation surgery in patients with metastatic melanoma

We examined the effectiveness of stereotactic radiation surgery (SRS) in 14 patients with brain metastasis in our hospital. The age of the patients ranged 45-85 years old (mean, 65). Brain metastasis was detected by neurological symptoms in seven patients and by regular imaging examination in the remaining patients. The number of metastatic lesions in the brain before SRS ranged 1-11 (median, 2). The treatment number of SRS was 1-4 times (median, 2). Six of 14 patients had neurological symptoms before SRS. Overall survival (OS) after SRS was 1.721.2 months (median, 8.2). The progression-free survival (PFS) after SRS was 0.9-10.5 months (median, 2.2). The result of univariate analysis showed that the application of two or more courses of SRS was significantly related to OS (P = 0.005). Single metastatic lesion (P = 0.051) and no extracranial lesion (P = 0.055) showed a slight tendency to be related to disease-free survival (DFS). Neither lactate dehydrogenase nor neurological symptoms were significantly related to OS or DFS. Although OS and DFS after SRS were not very long, the treatment of brain metastases has the potential to prevent neurological events. Repeating SRS may be accepted as a local therapy in the multimodal approach including new molecular targeting drugs for metastatic melanoma.ArticleJOURNAL OF DERMATOLOGY. 40(8):626-628 (2013)journal articl

Basal ryanodine receptor activity suppresses autophagic flux

The inositol 1,4,5-trisphosphate receptors (IP3Rs) and intracellular Ca2+ signaling are critically involved in regulating different steps of autophagy, a lysosomal degradation pathway. The ryanodine receptors (RyR), intracellular Ca2+-release channels mainly expressed in excitable cell types including muscle and neurons, have however not yet been extensively studied in relation to autophagy. Yet, aberrant expression and excessive activity of RyRs in these tissues has been implicated in the onset of several diseases including Alzheimer’s disease, where impaired autophagy regulation contributes to the pathology. In this study, we determined whether pharmacological RyR inhibition could modulate autophagic flux in ectopic RyR-expressing models, like HEK293 cells and in cell types that endogenously express RyRs, like C2C12 myoblasts and primary hippocampal neurons. Importantly, RyR3 overexpression in HEK293 cells impaired the autophagic flux. Conversely, in all cell models tested, pharmacological inhibition of endogenous or ectopically expressed RyRs, using dantrolene or ryanodine, augmented autophagic flux by increasing lysosomal turn-over (number of autophagosomes and autolysosomes measured as mCherry-LC3 punctae/cell increased from 70.37 ± 7.81 in control HEK RyR3 cells to 111.18 ± 7.72 and 98.14 ± 7.31 after dantrolene and ryanodine treatments, respectively). Moreover, in differentiated C2C12 cells, transmission electron microscopy demonstrated that dantrolene treatment decreased the number of early autophagic vacuoles from 5.9 ± 2.97 to 1.8 ± 1.03 per cellular cross section. The modulation of the autophagic flux could be linked to the functional inhibition of RyR channels as both RyR inhibitors efficiently diminished the number of cells showing spontaneous RyR3 activity in the HEK293 cell model (from 41.14% ± 2.12 in control cells to 18.70% ± 2.25 and 9.74% ± 2.67 after dantrolene and ryanodine treatments, respectively). In conclusion, basal RyR-mediated Ca2+-release events suppress autophagic flux at the level of the lysosomes