Fig. 1.

The β8 integrin cytoplasmic tail interacts with Band 4.1B. (A) Amino acid sequence alignment of the cytoplasmic domains of β integrin subunits that pair with αv integrin. Identical amino acids are highlighted in black or dark gray and conserved amino acids in light gray. β8cyto lacks primary amino acid sequence homology with other β subunits and does not contain the NPXY motif or the conserved juxtamembrane sequence. (B) A Y2H screen to identify proteins that interact selectively with β8cyto. The β8cyto sequence (white oval) was used to screen a human fetal brain cDNA library. Positive interactors were then screened by using the cytoplasmic tails of other integrins. (C) One example of a β8cyto-specific interacting positive, as determined by growth on selective media. (D) The β8cyto-specific positive shown in C encodes Band 4.1B. The portion of Band 4.1B that interacts with β8cyto is within the C-terminal portion (indicated by black bar).