The insulin receptors have specific shape that is compatible to the glucose molecules. The glucose molecules bind to these receptors, which tells the pancreas to release insulin in order to lower the blood glucose level. Any kind of change in the shape of these receptors because of mutation will hinder this cell communication and stop the insulin release. This will lead to high levels of blood sugar level.
Answer - In general Insulin receptors help by providing specific shape requirements for the glucose or sugar, so that it can produce insulin and release.
Just like the role in cells communication it gives role and commands to specific order. In this case its like the insulin receptors.
