In plants, posttranscriptional gene silencing (PTGS) has been reported for cytoplasmic RNAs from endogenous nuclear genes, transgenes, viruses, and, recently, for a viroid with nuclear replication and accumulation. However, phenomena of this kind have not been described for mitochondrial or chloroplastic RNAs. Here we show that viroids that replicate and accumulate in the chloroplast are also t...

Tal-effector nucleases (TALENs) are engineered proteins that can stimulate precise genome editing through specific DNA double-strand breaks. Sickle cell disease and β-thalassemia are common genetic disorders caused by mutations in β-globin, and we engineered a pair of highly active TALENs that induce modification of 54% of human β-globin alleles near the site of the sickle mutation. These TALEN...

A combination of environmental factors and endogenous cues trigger floral meristem initiation on the flanks of the shoot meristem. A plethora of regulatory genes have been implicated in this process. They function either as activators or as repressors of floral initiation. This review describes the mode of their action in a regulatory network that ensures the correct temporal and spatial contro...

It remains uncertain how the DNA sequence of mammalian genes influences the transcriptional response to extracellular signals. Here, we show that the number of CREB-binding sites (CREs) affects whether the related histone acetyltransferases (HATs) CREB-binding protein (CBP) and p300 are required for endogenous gene transcription. Fibroblasts with both CBP and p300 knocked-out had strongly atten...

Multiple copies of retroviral sequences are stably integrated in the genomes of many higher organisms, and are thus transmitted vertically to offspring via the germline (1). Most of these heritable viral genes are not expressed, and expression, when observed, is commonly limited to envelope (env) genes as demonstrated by the presence of cell surface and serum envelope glycoprotein (gp70) in mic...

Programmable control over an addressable global regulator would enable simultaneous repression of multiple genes and would have tremendous impact on the field of synthetic biology. It has recently been established that CRISPR/Cas systems can be engineered to repress gene transcription at nearly any desired location in a sequence-specific manner, but there remain only a handful of applications d...

Expression analyses of genes encoding sulfur-rich 10 kDa rice prolamins have not been reported to date although the entire genome of the model monocot plant has been sequenced in recent years. We isolated a 10 kDa rice prolamin gene, RP10, by genomic PCR, and the gene was registered in GenBank under the accession number AF294580. Genomic Southern-blot and bioinformatic study revealed that genes...

The main external time giver is the day-night cycle; however, signals from feeding and the activity/rest cycles can entrain peripheral clocks, such as the hippocampus, in the absence of light. Knowing that vitamin A and its derivatives, the retinoids, may act as regulators of the endogenous clock activity, we hypothesized that the nutritional deficiency of vitamin A may influence the locomotor ...

The NF-kappaB family of transcription factors is crucial for the expression of multiple genes involved in cell survival, proliferation, differentiation, and inflammation. The molecular basis by which NF-kappaB activates endogenous promoters is largely unknown, but it seems likely that it should include the means to tailor transcriptional output to match the wide functional range of its target g...