Switch #: SWTI000309

Switch type: Pre-assembly

Switch subtype: Composite binding site formation

Description:
Binding of Vitronectin (Vtn) to integrin receptors depends on pre-assembly of Integrin alpha-V (Itgav)-Integrin beta-3 (Itgb3) heterodimers, since association of the integrin alpha and beta subunits results in the formation of a composite binding site for the RGD motif in the ligand.

Participants:
(1) Integrin alpha-V (Itgav)
(2) Integrin beta-3 (Itgb3)
(3) Vitronectin (Vtn)

This is a sequential switch. The interactions in this switch take place in a defined order. The order is defined by numbers to the left of each interaction. More than one interaction can occur in each step, these interactions occur independently but are necessary for future step

1Interaction #1 Itgav - Itgb3

Interfaces
(1) FG-GAP repeat in Integrin alpha-V (Itgav)
(2) Integrin, beta chain _(37-460) in Integrin beta-3 (Itgb3)

2Interaction #2 Vtn - Interaction #1 Itgav - Itgb3

Requires Interaction #1 Itgav - Itgb3

Interfaces
(3) LIG_RGD motif (₆₄RGD₆₆) in Vitronectin (Vtn)
(4) Interaction #1 Itgav - Itgb3

(1) Integrin-linked kinase is required for vitronectin-mediated internalization of Streptococcus pneumoniae by host cells.
Bergmann et al. J. Cell. Sci. (2009)

Other switches involving interfaces
FG-GAP repeat - 13 more (view)
Integrin, beta chain - 13 more (view)
LIG_RGD - 12 more (view)