- The microphthalmia transcription factor and the related helix-loop-helix zipper factors TFE-3 and TFE-C collaborate to activate the tartrate-resistant acid phosphatase promoter. Mansky, K.C., Sulzbacher, S., Purdom, G., Nelsen, L., Hume, D.A., Rehli, M., Ostrowski, M.C. J. Leukoc. Biol. (2002)