In preferred embodiments, an MRT polypeptide comprises {HEAD ~ an amino acid sequence} of SEQ ID NO:2, {TAIL ~ SEQ ID NO:4}, SEQ ID NO:6, SEQ ID NO:8 or SEQID NO:14 
In preferred embodiments , an MRT polypeptide comprises { HEAD ~ an amino acid sequence } of SEQ ID NO:2 , { TAIL ~ SEQ ID NO:4 } , SEQ ID NO:6 , SEQ ID NO:8 or SEQID NO:14
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH