Although elongation of telomeres is thought to be the prime function of reactivated telomerase in cancers, this activity alone does not account for all of the properties that telomerase reactivation attributes to human cancer cells. Here, we uncover a link between telomerase and NF-κB, a master regulator of inflammation. We observe that while blocking NF-κB signalling can inhibit effects of telomerase overexpression on processes relevant to transformation, increasing NF-κB activity can functionally substitute for reduced telomerase activity. Telomerase directly regulates NF-κB-dependent gene expression by binding to the NF-κB p65 subunit and recruitment to a subset of NF-κB promoters such as those of IL-6 and TNF-α, cytokines that are critical for inflammation and cancer progression. As NF-κB can transcriptionally upregulate telomerase levels, our findings suggest that a feed-forward regulation between them could be the key mechanistic basis for the coexistence of chronic inflammation and sustained telomerase activity in human cancers.

We describe a genome-wide gain-of-function screen for regulators of NF-kappaB, and identify Rap1 (Trf2IP), as an essential modulator of NF-kappaB-mediated pathways. NF-kappaB is induced by ectopic expression of Rap1, whereas its activity is inhibited by Rap1 depletion. In addition to localizing on telomeres, mammalian Rap1 forms a complex with IKKs (IkappaB kinases), and is crucial for the ability of IKKs to be recruited to, and phosphorylate, the p65 subunit of NF-kappaB to make it transcriptionally competent. Rap1-mutant mice display defective NF-kappaB activation and are resistant to endotoxic shock. Furthermore, levels of Rap1 are positively regulated by NF-kappaB, and human breast cancers with NF-kappaB hyperactivity show elevated levels of cytoplasmic Rap1. Similar to inhibiting NF-kappaB, knockdown of Rap1 sensitizes breast cancer cells to apoptosis. These results identify the first cytoplasmic role of Rap1 and provide a mechanism through which it regulates an important signalling cascade in mammals, independent of its ability to regulate telomere function.

Although adeno-associated virus (AAV)-mediated gene therapy has been hindered by the small viral packaging capacity of the vector, trans-splicing AAV vectors are able to package twice the size of the vector genome. Unfortunately, the efficiency of current trans-splicing vectors is very low. Here we show that rational design of the gene splitting site has a profound influence on trans-splicing vector-mediated gene expression. Using mRNA accumulation as a guide, we generated a set of efficient trans-splicing vectors and achieved widespread expression of the 6-kb DeltaH2-R19 mini-dystrophin gene in skeletal muscle of mdx mice, a model for Duchenne muscular dystrophy. The dystrophic phenotype was ameliorated in both adult and aged mice. This demonstrates the use of trans-splicing vectors to efficiently express a large therapeutic structural protein. This strategy should be applicable to other large therapeutic genes or large transcription regulatory elements.

The underrepresentation of non-Europeans in human genetic studies so far has limited the diversity of individuals in genomic datasets and led to reduced medical relevance for a large proportion of the world's population. Population-specific reference genome datasets as well as genome-wide association studies in diverse populations are needed to address this issue. Here we describe the pilot phase of the GenomeAsia 100K Project. This includes a whole-genome sequencing reference dataset from 1,739 individuals of 219 population groups and 64 countries across Asia. We catalogue genetic variation, population structure, disease associations and founder effects. We also explore the use of this dataset in imputation, to facilitate genetic studies in populations across Asia and worldwide.

The success of many gene therapy applications hinges on efficient whole body transduction. In the case of muscular dystrophies, a therapeutic vector has to reach every muscle in the body. Recent studies suggest that vectors based on adeno-associated virus (AAV) are capable of body-wide transduction in rodents. However, translating this finding to large animals remains a challenge. Here we explored systemic gene delivery with AAV serotype-9 (AAV-9) in neonatal dogs. Previous attempts to directly deliver AAV to adult canine muscle have yielded minimal transduction due to a strong cellular immune response. However, in neonatal dogs we observed robust skeletal muscle transduction throughout the body after a single intravenous injection. Importantly, systemic transduction was achieved in the absence of pharmacological intervention or immune suppression and it lasted for at least 6 months (the duration of study). We also observed several unique features not predicted by murine studies. In particular, cardiac muscle was barely transduced in dogs. Many muscular dystrophy patients can be identified by neonatal screening. The technology described here may lead to an effective early intervention in these patients.