Mutations in the yeast mitochondrial RNA polymerase specificity factor, Mtf1, verify an essential role in promoter utilization.

The yeast mitochondrial RNA polymerase (RNAP) is a two-subunit enzyme composed of a catalytic core (Rpo41) and a specificity factor (Mtf1) encoded by nuclear genes. Neither subunit on its own interacts with promoter DNA, but the combined holo-RNAP recognizes and selectively initiates from promoters related to the consensus sequence ATATAAGTA. To pursue the question of why Rpo41, which resembles the single polypeptide RNAPs from bacteriophage T7 and T3, requires a separate specificity factor, we analyzed a collection of Mtf1 point mutations that confer an in vivo petite phenotype.

Characterization of Mu prophage lacking the central strong gyrase binding site: localization of the block in replication.

Bacteriophage Mu contains an unusually strong DNA gyrase binding site (SGS), located near the center of its genome, that is required for efficient Mu DNA replication (M. L. Pato, Proc.

Adenovirus type 5 precursor terminal protein-expressing 293 and HeLa cell lines.

HeLa and 293 cell lines that express biologically active adenovirus type 5 precursor terminal protein (pTP) have been made. The amount of pTP synthesized in these cell lines ranges from barely detectable to greater than that observed in cells infected with the wild-type virus. The pTP-expressing cell lines permit the growth of a temperature-sensitive terminal protein mutant virus sub100r at the nonpermissive temperature.

Myxococcus xanthus encodes an ATP-dependent protease which is required for developmental gene transcription and intercellular signaling.

The bsgA gene of Myxococcus xanthus plays an essential role in the regulation of early gene expression during fruiting body formation and sporulation. bsgA mutants behave as though unable to initiate a required cell-cell interaction and consequently fail to transcribe normal levels of many developmentally induced genes. We determined the nucleotide sequence of bsgA, which predicts a single gene encoding a 90.