Apoptosis is a very important life process; it plays an important role in embryonic development and morphogeny, mean while, it can maintain the stability of normal cell clusters and enhance the immune system in human organism. What’s more, it is of great importance to cell injury, cell senescence and tumorigenesis caused by diseases or poisoning. Apoptosis happens in two ways, namely endogenous and exogenous. The former way is considered to take place in all of the multicelled animals, while the latter belong particularly to vertebrates, it happens together with the adaptable immune system. Professor Xu Anlong and his team of the state key laboratory of resource utilization biological control of SYSU found that the exogenous signal channel of apoptosis, which is also called death receptors induced apoptosis channel, has developed in the immune system of amphioxus. This finding is different from the other researches that considered the channel appear only in vertebrates, proving that the exogenous signal channel of apoptosis is one hundred million years earlier. The study with Doctor Yuan Shaochun as its lead author （http://stke.sciencemag.org/cgi /content/full/sigtrans;3/139/ra66）was published in the form of Research Article on Science Signaling, the Supplement of Science as the recommended article on the topic of the evolution of signal transmission. Science Signaling is a journal that devoted to the topic of cell signaling.

Amphioxus, also called lancelet is one of the most primitive chordate that came into being about five hundred million years ago. As their genes maintain most of features of vertebrates, and they share almost the same developmental patterning vertebrates, they are considered to be one of the most important node in studying vertebrates’ origin and evolution. As he recognizes the unique feature of amphioxus, Professor Xu Anlong devoted himself to the research of the immune system of amphioxus. The article published on Science Signaling provides a brand new theory and evidence for exogenous signal channel of apoptosis, which turns over a new leaf for the future research of immune signal transmission.