TOKYO—Shock waves emanating from allegations of image manipulation and plagiarism in two Nature papers published in January continue to ripple through RIKEN, the Japanese institute at the center of the ongoing controversy. Last week, local media reported (in Japanese ) that questions have arisen about images in research papers published by three more members of a RIKEN committee charged with investigating the Nature papers. The news came a week after RIKEN announced it would investigate allegations  of image manipulation in papers published by Shunsuke Ishii, who resigned as chair of the investigating committee on 25 April.
Now, the Yomiuri Shimbun newspaper is reporting  that RIKEN President Ryoji Noyori has asked all laboratory and research group leaders to check all of their previous publications for doctored images and plagiarism. The newspaper quotes an unnamed RIKEN official as saying the directive covers at least 20,000 publications. There was no indication of a deadline for completing the reviews.
The still-unfolding controversy stems from instances of image manipulation and plagiarism in an article  and a letter  published online on 29 January in Nature by Haruko Obokata of RIKEN's Center for Developmental Biology in Kobe, together with colleagues at RIKEN and other institutions in Japan and at Harvard Medical School in Boston. The researchers reported finding a new, simple way of creating stem cells, called stimulus-triggered acquisition of pluripotency, which so far no other groups have been able to reproduce . The investigating committee, while still headed by Ishii, found numerous problems with the papers and concluded that two instances constituted research misconduct . Obokata is appealing the finding, claiming the problems resulted from innocent mistakes. RIKEN officials could not be reached for comment today because of a national holiday in Japan.