$filename = "input.txt";
open (IN, $filename) or die "Can't open file $filename : $! ";

$text = "";
while($line = <IN>)
{
	$text .= $line;
}

while($text =~ m/(TATAAT[ACGT]+(ATG[ACGT]+(TGA|TAG|TAA)))/g) #we check for DNA Strands along with TATA box #promoters..(TATAAT string) 
{
	print "$2\n";  
}