|
|
Active HSF1 also
binds to linear satellite III (SatIII) repeats of the sequence
GGAAT in chromosome 9, thus
resulting in the formation of so-called nuclear stress granules,
which active transcription sites for noncoding RNA of unknown
function.
The interactions of the DBD with DNA were best resolved in
thecrystal structure of the DBD-SatIII complex.
The alpha-3 helix inserts into major groove of DNA interacting
with GAA motif of SatIII repeats.
The
guanidinium group of Arg71 interacted with the guanine base in
the GAA motif via parallel hydrogen bonds.
The surrounding conserved residues Ser68, Gln72, Asn74, Met75
and Tyr76 stabilized the side chain conformation of Arg71 and
oriented helix α3 in the major groove by forming hydrogen bonds
to the phosphate backbone.
 a3
|