Genome-Wide Identification, Expression Analysis, and Subcellular Localization of Carthamus tinctorius bHLH Transcription Factors.

The basic helix-loop-helix (bHLH) family is the second largest superfamily of transcription factors that belongs to all three eukaryotic kingdoms. The key function of this superfamily is the regulation of growth and developmental mechanisms in plants. However, the bHLH gene family in Carthamus tinctorius has not yet been studied. Here, we identified 41 bHLH genes in Carthamus tinctorius that were classified into 23 subgroups. Further, we conducted a phylogenetic analysis and identified 10 conserved protein motifs found in the safflower bHLH family. We comprehensively analyzed a group of bHLH genes that could be associated with flavonoid biosynthesis in safflower by gene expression analysis, gene ontology annotation, protein interaction network prediction, subcellular localization of the candidate CtbHLH40 gene, and real-time quantitative expression analysis. This study provides genome-wide identification of the genes related to biochemical and physiological processes in safflower.

Phase I study of injectable, depot naltrexone for the relapse prevention treatment of opioid dependence.

BACKGROUND AND OBJECTIVES: We tested long-acting injectable depot naltrexone for its tolerability, pharmacokinetics, and safety in Phase I. METHODS: The Phase I trial enrolled 36 healthy participants in two panels (A, B). In Panel A, 24 subjects were randomly assigned to the high-dosage group (400 mg naltrexone, n=6; placebo, n=6) or low-dosage group (200 mg naltrexone, n=6; placebo, n=6). In Panel B, 12 subjects were randomized to take six doses of monthly injectable naltrexone (400 mg) or placebo. RESULTS: After a single injection of naltrexone 200 and 400 mg, means (SD) of naltrexone plasma concentrations were .57 (.28) ng/ml and 1.5 (.8) ng/ml 30 days post-injection. There was no effect of accumulation after multiple dosing. Eleven of 30 subjects (36.67%) who were administered injectable depot naltrexone reported a total of 12 adverse events (AEs). Seven of these 11 AEs were coded as possibly related with study medication. All treatment-related AEs were mild in severity. No serious treatment-related AEs occurred. DISCUSSION AND CONCLUSIONS: This long-acting formulation of injectable depot naltrexone is well tolerated, results in constant plasma concentration of naltrexone for at least 1 month. SCIENTIFIC SIGNIFICANCE: The tolerability and safety of long-acting injectable depot naltrexone are good.

Overexpression of a Novel Cytochrome P450 Promotes Flavonoid Biosynthesis and Osmotic Stress Tolerance in Transgenic Arabidopsis.

Flavonoids are mainly associated with growth, development, and responses to diverse abiotic stresses in plants. A growing amount of data have demonstrated the biosynthesis of flavonoids through multienzyme complexes of which the membrane-bounded cytochrome P450 supergene family shares a crucial part. However, the explicit regulation mechanism of Cytochrome P450s related to flavonoid biosynthesis largely remains elusive. In the present study, we reported the identification of a stress-tolerant flavonoid biosynthetic CtCYP82G24 gene from Carthamus tinctorius. The transient transformation of CtCYP82G24 determined the subcellular localization to the cytosol. Heterologously expressed CtCYP82G24 was effective to catalyze the substrate-specific conversion, promoting the de novo biosynthesis of flavonoids in vitro. Furthermore, a qRT-PCR assay and the accumulation of metabolites demonstrated that the expression of CtCYP82G24 was effectively induced by Polyethylene glycol stress in transgenic Arabidopsis. In addition, the overexpression of CtCYP82G24 could also trigger expression levels of several other flavonoid biosynthetic genes in transgenic plants. Taken together, our findings suggest that CtCYP82G24 overexpression plays a decisive regulatory role in PEG-induced osmotic stress tolerance and alleviates flavonoid accumulation in transgenic Arabidopsis.