Specific regulation of transcription of the discoidin gene family in Dictyostelium discoideum.

Dictyostelium discoideum strains that carry the dis mutations fail to express the family of developmentally regulated discoidin lectin genes during morphogenesis. We show here that this absence of discoidin lectin expression is due to the failure to transcribe the discoidin genes. Furthermore, the dis mutations appear to affect only discoidin expression and not the expression of other proteins during development, as assessed by a two-dimensional gel analysis of pulse-labeled proteins and by the accumulation of developmentally regulated enzymes. The dis mutations appear to define trans-acting regulatory loci, the products of which act at the transcriptional level to control specifically the developmental expression of the discoidin gene family.