The paper describes a previously unrecognized structure within the PKD1 gene product, polycystin. The study also demonstrates this structure binds specifically to PKD2. The data suggests that PKD1 and PKD2 associate physically and may be partners of a common signaling pathway. The study further suggests that one of the principle functions of PKD1 may be to regulate the activity of PKD2. The article goes on to show the presence of one or more naturally occurring mutations in either the PKD1 gene or the PKD2 gene results in the inability to interact with one another.
Normal kidneys are typically the size of a human fist.
Polycystic kidneys, however, can grow to be the size of a football or larger and weigh as much as 38 pounds each. PKD causes fluid-filled cysts to form in the kidneys, disrupting their ability to remove harmful toxins from the body. Cysts are sacs of fluid that cause the kidney to enlarge and hinder its filtering ability. A single cyst on a kidney attacked by PKD may be as large as an orange or a grapefruit. Cysts also squeeze blood vessels, forcing increased blood pressure.