Transcription factor IIIB generates extended DNA interactions in RNA polymerase III transcription complexes on tRNA genes

Journal Article · Thu Jun 01 00:00:00 EDT 1989 · Molecular and Cellular Biology; (USA)

DOI:https://doi.org/10.1128/MCB.9.6.2551· OSTI ID:5601728

Kassavetts, G A; Nguyen, L H; Geiduschek, E P ^[1]; Riggs, D L ^[2]; Negri, R ^[3]

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1. California Univ., San Diego, La Jolla, CA (USA). Dept. of Biology
2. California Univ., Irvine, CA (USA). Dept. of Chemistry
3. Centro di Studio per gli Acidi Nucleici del CNR, Rome (IT)

Transcription complexes that assemble on tRNA genes in a crude Saccharomyces cerevisiae cell extract extend over the entire transcription unit and approximately 40 base pairs of contiguous 5'-flanking DNA. The authors show here that the interaction with 5'-flanking DNA is due to a protein that copurifies with transcription factor TFIIIB through several steps of purification and shares characteristic properties that are normally ascribed to TFIIIB: dependence on prior binding of TFIIIC and great stability once the TFIIC-TFIIB-DNA complex is formed. SUP4 gene (tRNA/sup Tyr/) DNA that was cut within the 5'-flanking sequence (either 31 or 28 base pairs upstream of the transcriptional start site) was no longer able to stably incorporate TFIIB into a transcription complex. The TFIIB-dependent 5'-flanking DNA protein interaction was predominantly not sequence specific. The extension of the transcription complex into this DNA segment does suggest two possible explanations for highly diverse effects of flanking-sequence substitutions on tRNA gene transcription: either (i) proteins that are capable of binding to these upstream DNA segments are also potentially capable of stimulating or interfering with the incorporation of TFIIIB into transcription complexes or (ii) 5'-flanking sequence influences the rate of assembly of TFIIB into stable transcription complexes.

• OSTI ID: 5601728
• Journal Information: Molecular and Cellular Biology; (USA), Journal Name: Molecular and Cellular Biology; (USA) Vol. 9:6; ISSN MCEBD; ISSN 0270-7306
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL FUNCTIONS
BIOLOGICAL PATHWAYS
CHEMICAL BONDS
DNA SEQUENCING
ENZYMES
EUMYCOTA
FUNCTIONS
FUNGI
GENE REPRESSORS
GENES
KINETICS
MICROORGANISMS
NUCLEIC ACIDS
NUCLEOPROTEINS
NUCLEOTIDYLTRANSFERASES
ORGANIC COMPOUNDS
PHOSPHORUS-GROUP TRANSFERASES
PLANTS
POLYMERASES
PROTEINS
REACTION KINETICS
RNA
RNA POLYMERASES
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
STRUCTURAL CHEMICAL ANALYSIS
TRANSCRIPTION
TRANSCRIPTION FACTORS
TRANSFER RNA
TRANSFERASES
YEASTS