#!/usr/bin/perl

# http://perlmonks.org/?node_id=1146191

use strict;
use warnings;

my $sequence = 'AATGGTTTCTCCCATCTCTCCATCGGCATAAAAATACAGAATGATCTAACGAA';

$sequence =~ /(ATG.*?(?:TAG|TAA|TGA))(??{print "$1\n"})/;