Change default sender email address wordpress, This includes email being sent from a subdomains.

wordpresChangeSenderEmail.php

function setDefaultFromEmail(){
  	$url = "";
	$parse = parse_url(home_url());
	if (strpos($parse['host'], 'www') !== false) {
		$url = preg_replace('#^www\.(.+\.)#i', '$1', $parse['host']);
	}else{
		$url = $parse['host'];
	}
	$array = explode(".", $url);
	$uri = (array_key_exists(count($array) - 2, $array) ? $array[count($array) - 2] : "").".".$array[count($array) - 1];
	
	return "no-reply@" . $uri;
}
	
add_filter('wp_mail_from', 'setDefaultFromEmail');