Contains βTub85D sequence from -53bp to +156bp fused to lacZ. Also has an artificial BglII site between -38bp and -33bp of the βTub85D upstream sequence, created by the following nucleotide substitutions: G-34C, T-36A and T-37G. A 14bp region from -51bp to -38bp which is conserved in both D. melanogaster and D. hydei has been replaced by non-homologous sequence.