The structure of the insulin receptor in human cells has been finally pieced together by a group of researchers in Australia.
According to Michael Lawrence of the Walter and Eliza Hall Institute of Medical Research and his colleagues, the new research could pave the way for advancements in diabetes and cancer treatment.
When insulin binds to receptors on cells in the human body, it triggers a chain of events that result in glucose uptake from the blood.
"We're interested in how all this happens at the molecular level," ABC Science quoted Lawrence as saying.
In 2006, Lawrence and his research team used protein crystallography to image the insulin receptor protein.
They discovered one of the two elements that make up the initial binding site for insulin but the second element alluded them.
"The work at that time was an enormous advance, but there was still a missing piece that we were unable to find," said Lawrence.
Recently, they identified that second element.
"Insulin cannot bind either piece by itself, it requires the two pieces to be together as shown in order for any binding to the receptor to occur," said Lawrence.
After insulin has bound these two pieces, there are further interactions with the remainder of the receptor, before glucose uptake can be effected.
Lawrence said that the findings are important for researchers who are trying to develop insulin substitutes that can be taken orally, instead of injected.
He said it also might help in the development of insulin substitutes that are longer-lasting or quicker acting, reducing the number of times people with diabetes need to top up their insulin, or how quickly they need to respond to low blood sugar.
The findings have been published in the Proceedings of the National Academy of Sciences.