Pancreatic cells, in which SWELL1 is known to be expressed.WIKIMEDIA, POLARLYSA big piece of a long-standing puzzle—how cells maintain osmotic pressure via volume-regulated anion channels (VRACs)—appears to have been solved, as researchers reported in Cell today (April 10) having identified a key VRAC protein. Ardem Patapoutian of The Scripps Research Institute in La Jolla, California, and his colleagues found that this protein, which they’ve dubbed “SWELL1,” is a critical component of the osmotic channels that help keep cells from swelling until they explode.
“So far, nobody has been able to identify the proteins involved in mediating this widely-expressed current,” said Jorg Grandl of Duke University in Durham, North Carolina, who was not involved in this work. “To have a first report about one molecule that’s likely forming an ion channel that is mediating this current is a major step forward.”
Study coauthor Zhaozhu Qiu, a postdoctoral researcher in Patapoutian’s lab, first encountered VRACs while attending a conference talk that described how, for three decades, researchers have struggled to identify the proteins involved in the channels. VRACs keep the osmotic pressure of cells in check, using anions like chloride or iodide to generate an electrophysiological pulse when they’re open. These channels are ubiquitously expressed, making them difficult to isolate ...
