A 3-D View: IGF-1 with a Binding Protein
page allows you to view the 3 dimensional structure of the Insulin-like
growth factor 1 (IGF-1) protein bound by the Insulin-like growth
factor binding protein 5 (IGFBP5). Let's examine the structure and
interactions of these two proteins in more detail below.
and spin this complex.
IGF-1 in yellow and the binding protein in green. This binding protein
fifth identified for IGF-1) is thought to prohibit IGF-1 from
interacting with the
IGF-1 receptor, thus preventing the growth signal from being received (Zeslawski et al. 2001). Recent
studies have suggested there may be more diverse effects than simply
inhibitory, however (reviewed in Schneider et. al 2002).
here to view the disulfide bridges (in green) in this complex. There are three in
IGF-1 and 2 in IGFBP5. Notice how the disulfide bridges appear to
have a tremendous impact on the 3-dimensional structure of these two
the proteins by secondary structure characteristics. Alpha
helices are pink, and beta sheets are yellow.
here to see which portion of IGF-1 is responsible for binding with
various binding proteins. The amino acids 1-16 in IGF-1 have been shown
be important in binding protein interactions (Bayne et. al 1989); this button will make
these residues yellow.
here to see how IGF-1 binds with its cellular receptor, IGF-1R. Amino
and 28-37 are recognized as crucial for binding (Bayne et. al 1989); these residues
will become orange.
here to view the complex colored according to "anisotropic
temperature." Essentially, parts of the protein that are more capable
of movement are red, and more immobile portions of the protein are blue (Silva and Marcey 2007).
© Copyright 2010 Department of Biology, Davidson College,
Davidson, NC 28036