A 149bp fragment containing the Tag:V5 tag sequence fused in frame to some mh coding sequence (that was PCR amplified from the 'pW8- V5:mh ' vector) is joined to a 2341bp genomic fragment covering the rest of the mh coding sequence and 1531bp downstream of the stop codon excised from the CH322S124H21 BAC using SacII and XbaI. Expressed under the control of UASp regulatory sequences.