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.
Schematic representation of spatial arrangements between two adjacent protofilaments, with the r and h directions indicated as discussed in the text (α-tubulins and β-tubulins are represented as white and dark ribbons, respectively). The figure was generated with PyMOL (91).
