Yeast Mitochondrial Transcription Factor Mtf1 Determines the Precision of Promoter-Directed Initiation of RNA Polymerase Rpo41.
Despite their clear T7-bacteriophage origin, mitochondrial RNA polymerases have evolved to require transcription factors. All mitochondrial polymerases contain an extra N-terminal domain that has no counterpart in the self-proficient phage enzyme, which is therefore hypothesized to interact with transcription factors. We studied a series of N-terminal deletion mutants of yeast mitochondrial RNA polymerase, Rpo41, and have found that the N-terminal region does not abolish the effects of Mtf1; rather it contributes directly to enzyme catalysis. Mtf1 can rescue the defective Rpo41 enzymes resulted from N-terminal domain deletions. Although Rpo41 appears to have retained all promoter recognition elements found in T7 RNAP, the elements are not independently functional, and Mtf1 is necessary and sufficient for holoenzyme promoter-directed transcription activity.
Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, 78712, United States of America.
Xu
X
Yang
Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, 78712, United States of America.
Hae Ryung
HR
Chang
Department of Pharmacology and Toxicology, Sealy Center for Structural Biology, University of Texas Medical Branch, Galveston, TX, 77555, United States of America.
Y Whitney
YW
Yin
D000595:Amino Acid Sequence; D001483:Base Sequence; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016415:Sequence Alignment; D017384:Sequence Deletion; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation
C071720:MTF1 protein, S cerevisiae; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D012321:DNA-Directed RNA Polymerases; C487996:RPO41 protein, S cerevisiae