TOKYO - A Japanese stem cell scientist, under pressure over inconsistencies in her groundbreaking research, has agreed to retract one of the two papers published in the respected journal Nature, reports said Thursday. Haruko Obokata, 30, was feted after unveiling research that appeared to show a straightforward way to re-programme adult cells to become a kind of stem cell. Stem cells are precursors that are capable of developing into any other cell in the human body, and a readily manufacturable supply of them could one day help meet a need for transplant tissues, or even whole organs. But within weeks of her paper on so-called Stimulus-Triggered Acquisition of Pluripotency (STAP) cells being published, questions began to emerge, with fellow scientists saying they could not replicate her results. Riken, the respected research institute that sponsored the study, has urged her to withdraw her two papers, after concluding that she fabricated at least some of the data.