Amitochondriate amoebae and the evolution of DNA-dependent RNA polymerase II.

ABSTRACT: Unlike parasitic protist groups that are defined by the absence of mitochondria, the Pelobiontida is composed mostly of free-living species. Because of the presence of ultrastructural and cellular features that set them apart from all other eukaryotic organisms, it has been suggested that pelobionts are primitively amitochondriate and may represent the earliest-evolved lineage of extant protists. Analyses of rRNA genes, however, have suggested that the group arose well after the diversification of the earliest-evolved protists. Here we report the sequence of the gene encoding the largest subunit of DNA-dependent RNA polymerase II (RPB1) from the pelobiont Mastigamoeba invertens. Sequences within RPB1 encompass several of the conserved catalytic domains that are common to eubacterial, archa

SUBMITTER: Stiller JW 

PROVIDER: S-EPMC21715 | biostudies-literature | 1998 Sep

REPOSITORIES: biostudies-literature