|
Figure 6.
Figure 6. Prediction of PH Domain 3-Phosphoinositide
SpecificityPH domains shown to recognize PI 3-kinase products
([15]) are aligned with Grp1-PH and Btk-PH (A) or DAPP1-PH (B),
according to whether they are predicted (see text) to make
direct side chain contacts with the 5-phosphate of
Ins(1,3,4,5)P[4]. Elements of secondary structure are delineated
with gray arrows (β strands) or a black bar (the C-terminal α
helix). Residues are colored when their side chain is involved
in interactions with Ins(1,3,4,5)P[4] in the Btk-PH, Grp1-PH, or
DAPP1-PH complex structures. Yellow represents interaction with
the 1-phosphate; red, the 3-phosphate; green, the 4-phosphate;
and blue, the 5-phosphate. Color coding is predicted for PH
domains of unknown structure. The 3-phosphoinositide binding
motif ([15]) in the β1/β2 region is also color coded as
described above. In (A), PH domains with names underlined are
known to select PtdIns(3,4,5)P[3] over PtdIns(3,4)P[2]. Others
are predicted to do so. In (B), DAPP1-PH and PKB-PH are both
known to bind almost equally to PtdIns(3,4,5)P[3] and
PtdIns(3,4)P[2]. Others are predicted to do so.
|
