NUCLEOTIDE AND PREDICTED AMINO-ACID-SEQUENCE OF A NEW MEMBER OF THE RAS GENE FAMILY FROM THE SLIME-MOLD PHYSARUM-POLYCEPHALUM

A second ras homologue, designated Ppras2, has been isolated from Phys arum polycephalum mixed amoebae and flagellates cDNA library. Ppras2 e ncodes a protein of 193 amino acids of a calculated M(r) of 21633. The deduced amino acid sequence is highly homologous to Ppras1 and other ras genes from slime molds. The amino acid sequence at the C-terminus of the putative protein suggests that like other slime mold ras protei ns but not the ones from other organisms, it is modified by geranylger anylation rather than farnesylation, it is unpalmitoylated and contain s a putative lysine-rich domain.