Chinese scientists greet the year of the pigSoon, not only fireflies will spread light on the dark, but also the sausages from our plates! Fluorescence is not such a rare occurrence in the nature, even if not many of us have witnessed it.
Lightning bug females are the most known example, but many other fluorescent organisms are found in the sea. Even some molecules from the human body can have an intrinsic fluorescence. Bilirubin, for instance, a protein from the gall bladder, is highly fluorescent when bound to a specific site on serum albumin.
Zinc protoporphyrin, formed in developing red blood cells instead of hemoglobin when iron is unavailable or lead is present, has a bright fluorescence. The protein named aequorin, from the luminescent jellyfish Aequorea victoria and many other marine organisms, produces a blue glow in the presence of Ca2+ ions, due to a chemical reaction, that's why it has been used to image calcium flow in cells in real time.
Aequorin made researcher to further investigate A. victoria, finding the Green Fluorescent Protein (GFP), now an extremely important research tool. GFP and related proteins are used as reporters for any number of biological events including such things as sub-cellular localization.
Levels of gene expression are sometimes measured by linking a gene for GFP production to another gene. Now, a Chinese research team at the Northeast Agricultural University in Harbin have successfully bred partially green fluorescent pigs in order to boost stem cell research. The researchers managed to breed three transgenic pigs by injecting the genes of GFP into embryonic pigs.
"The mouth, trotters and tongue of the pigs are green under ultraviolet light," said Professor Liu Zhonghua.
"Genetic material from jellyfish was injected into the womb of a sow which gave birth to the three pigs 114 days later in Harbin," he said.
China is the fourth country after US, South Korea and Japan in succeeding this and it celebrates the start of the Year of the Pig in February. It will be a bright one, that's for sure!