This post has been updated to indicate that the Mass General-led team examined approximately 1,000 nuclear genes that encode mitochonrial proteins, not nuclear proteins as was written in error.
In a paper published online in advance in Science this week, an international team led by investigators at the University of California, San Diego, shows that a "mutation of either TMEM138 or TMEM216 causes a phenotypically indistinguishable human ciliopathy, Joubert syndrome." Further, the team goes on to show that "expression of the two genes is mediated by a conserved regulatory element in the noncoding intergenic region," and that their coordinated expression "is important for their interdependent cellular role in vesicular transport to primary cilia."
Over in this week's issue, researchers at the University of California, Irvine, and their collaborators in Paris report their identification of 1,331 beneficial mutations in representative genome sequences culled from 115 populations of Escherichia coli experimentally evolved at 42.2°C for 2,000 generations. "Our experiment uncovered a set of primary functional targets of high temperature, but we estimate that many other beneficial mutations could contribute to similar adaptive outcomes," the authors write.
And in Science Translational Medicine, an international team led by investigators at Massachusetts General Hospital in Boston presents its "MitoExome" sequencing study on the mtDNA and exons of approximately 1,000 nuclear genes that encode mitochonrial proteins, through which they "prioritized rare mutations predicted to disrupt function." Of the 42 unrelated infants with clinical and biochemical evidence of mitochondrial oxidative phosphorylation disease the team studied, 13 showed mutations in nuclear genes not previously linked to disease. "The pathogenicity of two such genes, NDUFB3 and AGK, was supported by complementation studies and evidence from multiple patients, respectively," the authors write, adding that their "results underscore the potential and challenges of deploying NGS [next-generation sequencing] in clinical settings."