Scientists and doctors continue to find themselves baffled by Kawasaki disease (KD), an inflammatory disorder that represents the leading cause of pediatric heart problems in the developed world. “The cause of KD has remained unknown for more than 40 years since the first description of the disease by Dr. Kawasaki, and so there is no evidence-based therapeutic strategy,” says Yoshihiro Onouchi of the RIKEN Center for Genomic Medicine in Yokohama.
Onouchi has partnered with other scientists in Japan and the United States to identify chromosomal regions containing genes potentially associated with this condition, uncovering strong evidence that KD arises in part from improper regulation of the immune system. Based on this hypothesis, he and his colleagues recently examined loci within chromosomal region 4q35, which contains a diverse array of genes relevant to this process1.
The researchers were especially interested in the gene encoding caspase-3 (CASP3), an enzyme that participates in the initiation of programmed cell death and thereby helps to mitigate the extent of T cell-mediated immune responses. By comparing data from a cohort of Japanese individuals affected with KD relative to their unaffected counterparts, they were able to identify more than two dozen sequence variations near CASP3 that appear to preferentially associate with disease onset.
Functional analysis of the gene revealed the presence of an ‘enhancer’, a stretch of DNA where regulatory proteins can bind to help ratchet up expression levels, surrounding one of the variants identified in this initial screen. The researchers determined that the genomic sequence alteration linked with KD appears to impair enhancer binding by the transcriptional regulator nuclear factor of activated T cells (NFAT), and this reduced NFAT binding in turn leads to significantly reduced CASP3 expression. Importantly, this variant is also significantly associated with disease susceptibility in European populations.
Onouchi and colleagues have previously identified another KD-associated variation (or SNP) in the gene encoding inositol 1,4,5-trisphosphate 3 kinase-C (ITPKC), an enzyme that downregulates a T cell signaling cascade in which calcium ion (Ca2+) flux is coupled with NFAT activation2. In combination, these findings suggest that NFAT may offer a promising drug target. “The calcineurin enzyme plays a key role in the Ca2+/NFAT pathway, and we are now interested in the potential of calcineurin inhibitors like cyclosporin A as a therapeutic option,” says Onouchi. “Our team is now collaborating with several medical institutes in Japan in an attempt to evaluate the effectiveness of cyclosporin A on refractory KD cases.”
The corresponding author for this highlight is based at the Laboratory for Cardiovascular Disease, RIKEN Center for Genomic Medicine
Journal information1. Onouchi, Y., Ozaki, K., Burns, J.C., Shimizu, C., Hamada, H., Honda, T., Terai, M., Honda, A., Takeuchi, T., Shibuta, S. et al. Common variants in CASP3 confer susceptibility to Kawasaki disease. Human Molecular Genetics published online 10 May 2010 (doi: 10.1093/hmg/ddq176)
2. Onouchi, Y., Gunji, T., Burns, J.C., Shimizu, C., Newburger, J.W., Yashiro, M., Nakamura, Y., Yanagawa, H., Wakui, K., Fukushima, Y. et al. ITPKC functional polymorphism associated with Kawasaki disease susceptibility and formation of coronary artery aneurysms. Nature Genetics 40, 35–42 (2008)
gro-pr | Research asia research news
A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to developing a new active ingredient against chronic infections
21.08.2017 | Deutsches Zentrum für Infektionsforschung
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences