Acts as a transcriptional activator or repressor. Implicated in the regulation of cell-type specific gene expression and play a role in inductive events during lens development (By similarity). Homodimer or heterodimer with other bHLH-Zip transcription factors. Binds DNA as a homodimer or a heterodimer (By similarity). Expressed in the somites at stage 19 onwards. Expressed in the developing hindbrain between neural plate at stage 32. Expressed in the ventral blood islands from stage 22 until stage 28. Expressed in the condensing pronephros at stage 24. Expressed in the pronephric tubules at stage 33. Expressed in the presumptive lens-forming ectoderm (PLE) at stage 22 and during lens formation. Expressed in the invaginating placode at stage 28. Expressed in lens epithelia at stage 33. Expressed in the rhombencephalon at least until stage 40. Expressed in the olfactory bulb and the thalamus at stage 43. Expressed in the neural crest cells. Belongs to the bZIP family. Maf subfamily.