Research into how breast milk is produced could help in the search for a breast cancer cure.
Melbourne scientists have discovered the protein MCL-1 is vital for keeping milk-producing cells alive and sustaining milk production in the breast.
Without milk, mammals cannot survive, making MCL-1 essential to their survival.
"The bottom line is that this is a really important survival protein in breast tissue," said Geoff Lindeman from the Walter and Eliza Hall Institute.
"We've discovered that it's essentially the key protein that helps keep breast tissue alive during lactation."