An Hsp83 promoter drives expression of 6 tandem repeats of a 72bp fragment from roX2, which encodes the stem-loop region. The repeats of the stem loop sequence are in antisense orientation. An Act5C fragment provides the polyA site.
roX2A-SL-6.Hsp83 shows no rescue of the lethality of roX[-] males (roX1ex6 Df(1)52 P{w+4Δ4.3}/Y).