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<textarea class="form-control" name="input-data" id="input-data" rows=
+"15"></textarea>

...
                    <button type="submit" class="btn btn-primary btn-l
+g" id="submit-sig1" name="query-sig1" value="SFssO806NA96rvTzMiLyoQ" 
+data-toggle="tooltip" title="Search NLSdb for all NES/NLS sequences s
+imilar to one or more query signal sequence(s).">Find similar NES/NLS
+ in NLSdb</button>
                    <button type="submit" class="btn btn-primary btn-l
+g" id="submit-sig2" name="query-sig2" value="SFssO806NA96rvTzMiLyoQ" 
+data-toggle="tooltip" title="Evaluate one or more query signal sequen
+ce(s) based on the number of nuclear and non-nuclear protein sequence
+s they match.">Evaluate NES/NLS</button>
                </div>

use WWW::Mechanize;

...
my $result = $mech->content();
print $result;