Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Three-dimensional structures of cyclins showing the location of conserved and variable secondary structure elements. A, human cyclin A1-CDK2 complex; B, human B1 cyclin; C, yeast B1 cyclin; D human B3 cyclin; E human cyclin D1-CDK4 complex; F, human E1 cyclin. Secondary structures: replacement number significantly greater than expected is marked "+". CDK molecules are in red; cyclin regions within gapless alignment are in blue.
