“Progress in science is driven by new technologies, new discoveries, new ideas – in that order” (S. Brenner). This quote by one of the greatest biologists of the 20th century came to my mind while reading a curious paper recently published in Nature. To sum up, a group from Taiwan has discovered that some cells can divide despite an absence of DNA replication.
This kind of splitting, called “asynthetic fission”, is very different from the classic modes of cell division described in multicellular organisms (mitosis in somatic cells and meiosis in germ cells). Chen and colleagues spotted this third way by experimenting on zebrafish with the help of CRISPR and multicolor barcoding, an amazing technique where colored cells can be tracked in live animals for days or weeks.
The authors propose that “asynthetic fission is used as an efficient mechanism for expanding epithelial coverage during rapid growth”. We do not yet know if it happens only in developing larvae of zebrafish, the superstar animal of many experiments in biology. Nor do we know if it occurs only in epidermal cells. But nature is an inexhaustible source of awe and many more discoveries and ideas will keep flowing from apparently weird papers made possible by the invention of CRISPR.