- Mice deficient for the ets transcription factor elk-1 show normal immune responses and mildly impaired neuronal gene activation. Cesari, F., Brecht, S., Vintersten, K., Vuong, L.G., Hofmann, M., Klingel, K., Schnorr, J.J., Arsenian, S., Schild, H., Herdegen, T., Wiebel, F.F., Nordheim, A. Mol. Cell. Biol. (2004)