Structure, expression, and inactivation by gene disruption of the Dictyostelium discoideum prespore gene EB4

We present the nucleotide sequence of the cell type specific prespore gene EB4 which encodes a protein containing a hydrophobic leader sequence and two distinct domains of amino acid repeats. By RNase protection experiments we have determined the genomic organization of the gene which differs substantially from the previously published data. An antibody directed against one of the repeat structures (hexamer repeat) specifically reacts with a developmentally regulated antigen of 58 kd. Gene disruption transformants were obtained by transformation with a genomic DNA fragment. The transformants express a 3′ truncated mRNA and do not react with the anti‐hexamer antibody. So far, we could not detect any phenotypic aberrations in the transformed cell line.