{HEAD ~ The invention} also provides {TAIL ~ an isolated or purified preparation} of an MRT polypeptide 
provides
{ HEAD ~ The invention } also provides { TAIL ~ an isolated or purified preparation } of an MRT polypeptide
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH