Nature Communications 5: Article number: 5561 (2014); Published: 28 November 2014; Updated: 21 October 2015.

Figure 2e of this Article shows an incorrect transmission electron microscope image. This image was taken by Mr Kenneth Ng from the group of Dr Gang Zheng at the University of Toronto from the sample prepared by Joseph Tang and co-workers for a different project. The correct image, which appears below, was taken by the imaging core facility at the Institute of Cellular and Organismic Biology, Academia Sinica, Taiwan, from the sample reported in this paper. Both samples were prepared using the same procedure described in the methods section of the article.

Figure 2.