Identification of human Kir2.2 (KCNJ12) gene encoding functional inward rectifier potassium channel in both mammalian cells and Xenopus oocytes

AbstractArginine residue at position 285 (R285) in the intracellular C-terminal domain of inward rectifier potassium channel Kir2.2 is conserved in many species, but missing in previously reported human Kir2.2 sequences. We here identified the human Kir2.2 gene in normal individuals, which contained R285 in the deduced amino-acid sequence (hKir2.2/R285). All 30 individuals we examined were homozygous for Kir2.2/R285 gene. The hKir2.2/R285 was electrophysiologically functional in both mammalian cells and Xenopus oocytes. However, the hKir2.2 missing R285 was functional only in Xenopus oocytes, but not in mammalian cells. Thus, R285 in Kir2.2 is important for its functional expression in mammalian cells

Versatile Assays for High Throughput Screening for Activators or Inhibitors of Intracellular Proteases and Their Cellular Regulators

BACKGROUND: Intracellular proteases constitute a class of promising drug discovery targets. Methods for high throughput screening against these targets are generally limited to in vitro biochemical assays that can suffer many technical limitations, as well as failing to capture the biological context of proteases within the cellular pathways that lead to their activation. METHODS #ENTITYSTARTX00026; FINDINGS: We describe here a versatile system for reconstituting protease activation networks in yeast and assaying the activity of these pathways using a cleavable transcription factor substrate in conjunction with reporter gene read-outs. The utility of these versatile assay components and their application for screening strategies was validated for all ten human Caspases, a family of intracellular proteases involved in cell death and inflammation, including implementation of assays for high throughput screening (HTS) of chemical libraries and functional screening of cDNA libraries. The versatility of the technology was also demonstrated for human autophagins, cysteine proteases involved in autophagy. CONCLUSIONS: Altogether, the yeast-based systems described here for monitoring activity of ectopically expressed mammalian proteases provide a fascile platform for functional genomics and chemical library screening

The role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs

We investigated the role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs. Twenty-five cases of rectal polypoid lesions in dogs who underwent surgery after endoscopic and EUS assessment were studied. The invasion depth of the polypoid lesion was classified as M stage (lesions in the mucosa only), SM stage (lesions in the mucosa and submucosa), and MP stage (lesions extending to the muscularis propria). Transabdominal ultrasound was performed in nine cases, but not all were evaluated in detail. EUS provided detailed images for all cases and showed a significant correlation with surgical pathology in the T stage (accuracy, 92%; κ = 0.77). As per classification by invasion depth, inflammatory polyps were only M polypoid lesions, whereas SM and MP polypoid lesions were only adenocarcinomas (P < 0.05). The average survival time according to specific condition was as follows: 1,235 days for inflammatory polyps, and 804 days for M adenocarcinoma. The survival time of two SM adenocarcinoma cases was 756 and 2,114 days, respectively, and the survival time of two MP adenocarcinoma cases was 16 and 42 days, respectively. EUS were useful for the evaluation of rectal polypoid lesions in dogs, whereas transabdominal ultrasound was not. Determination of the invasion depth of polypoid lesions using EUS may be useful for the evaluation of malignancy and prognosis

Synthesis of 4,4-Dihydrodithienosilole and Its Unexpected Cyclodimerization Catalyzed by Ni and Pt Complexes

4,4-Dihydrodithienosilole (<b>DTSH</b>_<b>2</b>) was isolated from a mixture of 3,3′-dibromobithiophene, <i>n</i>-BuLi, and H₂SiCl₂ and was fully characterized. The reaction of <b>DTSH</b>_<b>2</b> with a Pt(0) complex, prepared <i>in situ</i> from [Pt­(PCy₃)₂] and DPPE (1,2-bis­(diphenylphosphino)­ethane), produced a bis­(silyl)platinum complex [Pt­(DTSH)₂(dppe)] (<b>1</b>) with two hydrodithienosilole ligands. <b>DTSH</b>_<b>2</b> undergoes cyclodimerization accompanied by skeletal rearrangement to afford a cis-fused bicyclic compound (<b>2</b>) upon heating the solution in the presence of a catalytic amount of <b>1</b> or [Ni­(PPh₃)₄]. The product has a Si–Si bond that bridges two Si atoms, separated by 2.309(1) Å. Bicyclic disilane <b>2</b> forms the Pt complex (<b>3</b>) with two Si ligands and retaining the 10-membered macrocycle ligand via the Si–Si bond cleavage