The C-terminal domain of transcription factor IIIA interacts differently with different 5S RNA genes

1989 ◽  
Vol 9 (2) ◽  
pp. 499-514
Author(s):  
Y Y Xing ◽  
A Worcel
Keyword(s):  
Transcription Factor ◽  
Site Directed Mutagenesis ◽  
5S Rna ◽  
Transcription Factor Iiia ◽  
5S Dna ◽  
Type Site ◽  
Single Trace ◽  
Dna Complex ◽  
5S Rna Genes ◽  
Rna Genes

DNase I footprints and affinity measurements showed that the C-terminal arm of Xenopus transcription factor IIIA interacts differently with different Xenopus 5S DNAs, forming three distinct types of transcription factor IIIA-5S DNA complexes: a somatic type, a major-oocyte (and pseudogene) type, and a trace-oocyte type. Site-directed mutagenesis on the major-oocyte 5S gene revealed that somatic-type changes at positions 53, 55, and 56 changed the structure of the transcription factor IIIA-5S DNA complex from major-oocyte to somatic, and a single trace-oocyte change at position 56 caused the change from major-oocyte to trace-oocyte complex. We further show that the somatic-type changes are accompanied by a marked enhancement in the rate of 5S RNA transcription, and we discuss the possible biological relevance of these findings.

scholarly journals The C-terminal domain of transcription factor IIIA interacts differently with different 5S RNA genes.

1989 ◽  
Vol 9 (2) ◽  
pp. 499-514 ◽  
Author(s):  
Y Y Xing ◽  
A Worcel
Keyword(s):  
Transcription Factor ◽  
Site Directed Mutagenesis ◽  
5S Rna ◽  
Transcription Factor Iiia ◽  
5S Dna ◽  
Type Site ◽  
Single Trace ◽  
Dna Complex ◽  
5S Rna Genes ◽  
Rna Genes

DNase I footprints and affinity measurements showed that the C-terminal arm of Xenopus transcription factor IIIA interacts differently with different Xenopus 5S DNAs, forming three distinct types of transcription factor IIIA-5S DNA complexes: a somatic type, a major-oocyte (and pseudogene) type, and a trace-oocyte type. Site-directed mutagenesis on the major-oocyte 5S gene revealed that somatic-type changes at positions 53, 55, and 56 changed the structure of the transcription factor IIIA-5S DNA complex from major-oocyte to somatic, and a single trace-oocyte change at position 56 caused the change from major-oocyte to trace-oocyte complex. We further show that the somatic-type changes are accompanied by a marked enhancement in the rate of 5S RNA transcription, and we discuss the possible biological relevance of these findings.

Regular arrangement of nucleosomes on 5S rRNA genes in Xenopus laevis

1983 ◽  
Vol 3 (4) ◽  
pp. 720-730
Author(s):  
D Young ◽  
D Carroll
Keyword(s):  
Xenopus Laevis ◽  
Chromatin Structure ◽  
Micrococcal Nuclease ◽  
Rrna Genes ◽  
Dna Repeats ◽  
5S Rna ◽  
5S Dna ◽  
Regular Arrangement ◽  
5S Rna Genes ◽  
Rna Genes

The chromatin structure of the oocyte-type 5S RNA genes in Xenopus laevis was investigated. Blot hybridization analysis of DNA from micrococcal nuclease digests of erythrocyte nuclei showed that 5S DNA has the same average nucleosome repeat length, 192 +/- 4 base pairs, as two Xenopus satellite DNAs and bulk erythrocyte chromatin. The positions of nuclease-sensitive regions in the 5S DNA repeats of purified DNA and chromatin from erythrocytes were mapped by using an indirect end-labeling technique. Although most of the sites cleaved in purified DNA were also cleaved in chromatin, the patterns of intensities were strikingly different in the two cases. In 5S chromatin, three nuclease-sensitive regions were spaced approximately a nucleosome length apart, suggesting a single, regular arrangement of nucleosomes on most of the 5S DNA repeats. The observed nucleosome locations are discussed with respect to nucleotide sequences known to be important for expression of 5S RNA. Because the preferred locations appear to be reestablished in each repeating unit, despite spacer length heterogeneity, we suggest that the regular chromatin structure reflects the presence of a sequence-specific DNA-binding component on inactive 5S RNA genes.

Proteolytic footprinting of transcription factor TFIIIA reveals different tightly binding sites for 5S RNA and 5S DNA

1993 ◽  
Vol 13 (9) ◽  
pp. 5149-5158
Author(s):  
D F Bogenhagen
Keyword(s):  
Transcription Factor ◽  
Binding Site ◽  
Zinc Fingers ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
5S Rna ◽  
Transcription Factor Iiia ◽  
Tryptic Fragment ◽  
N Terminus ◽  
5S Dna

Transcription factor IIIA (TFIIIA) employs an array of nine N-terminal zinc fingers to bind specifically to both 5S RNA and 5S DNA. The binding of TFIIIA to 5S RNA and 5S DNA was studied by using a protease footprinting technique. Brief treatment of free or bound TFIIA with trypsin or chymotrypsin generated fragments which were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Fragments retaining the N terminus of TFIIA were identified by immunoblotting with an antibody directed against the N terminus of TFIIIA. Proteolytic footprinting of TFIIIA complexed with 5S DNA derivatives reinforced other evidence that the three N-terminal zinc fingers of TFIIIA bind most tightly to 5S DNA. Proteolytic footprinting of TFIIIA in reconstituted 7S ribonucleoprotein particles revealed different patterns of trypsin sensitivity for TFIIIA bound to oocyte versus somatic 5S RNA. Trypsin cleaved TFIIIA between zinc fingers 3 and 4 more readily when the protein was bound to somatic 5S RNA than when it was bound to oocyte 5S RNA. A tryptic fragment of TFIIIA containing zinc fingers 4 through 7 remained tightly associated with somatic 5S RNA. Zinc fingers 4 through 7 may represent a tightly binding site for 5S RNA in the same sense that fingers 1 through 3 represent a tightly binding site for 5S DNA.

scholarly journals Chromosomal organization of Xenopus laevis oocyte and somatic 5S rRNA genes in vivo.

1992 ◽  
Vol 12 (1) ◽  
pp. 45-55 ◽  
Author(s):  
C C Chipev ◽  
A P Wolffe
Keyword(s):  
Xenopus Laevis ◽  
Rrna Genes ◽  
Dna Repeats ◽  
5S Rna ◽  
Chromosomal Organization ◽  
Dna Repeat ◽  
5S Dna ◽  
Nuclease Digestion ◽  
5S Rna Genes ◽  
Rna Genes

We describe the chromosomal organization of the major oocyte and somatic 5S RNA genes of Xenopus laevis in chromatin isolated from erythrocyte nuclei. Both major oocyte and somatic 5S DNA repeats are associated with nucleosomes; however, differences exist in the organization of chromatin over the oocyte and somatic 5S RNA genes. The repressed oocyte 5S RNA gene is protected from nuclease digestion by incorporation into a nucleosome, and the entire oocyte 5S DNA repeat is assembled into a loosely positioned array of nucleosomes. In contrast, the potentially active somatic 5S RNA gene is accessible to nuclease digestion, and the majority of somatic 5S RNA genes appear not to be incorporated into positioned nucleosomes. Evidence is presented supporting the stable association of transcription factors with the somatic 5S RNA genes. Histone H1 is shown to have a role both in determining the organization of nucleosomes over the oocyte 5S DNA repeat and in repressing transcription of the oocyte 5S RNA genes.

scholarly journals Proteolytic footprinting of transcription factor TFIIIA reveals different tightly binding sites for 5S RNA and 5S DNA.

1993 ◽  
Vol 13 (9) ◽  
pp. 5149-5158 ◽  
Author(s):  
D F Bogenhagen
Keyword(s):  
Transcription Factor ◽  
Binding Site ◽  
Zinc Fingers ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
5S Rna ◽  
Transcription Factor Iiia ◽  
Tryptic Fragment ◽  
N Terminus ◽  
5S Dna

Transcription factor IIIA (TFIIIA) employs an array of nine N-terminal zinc fingers to bind specifically to both 5S RNA and 5S DNA. The binding of TFIIIA to 5S RNA and 5S DNA was studied by using a protease footprinting technique. Brief treatment of free or bound TFIIA with trypsin or chymotrypsin generated fragments which were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Fragments retaining the N terminus of TFIIA were identified by immunoblotting with an antibody directed against the N terminus of TFIIIA. Proteolytic footprinting of TFIIIA complexed with 5S DNA derivatives reinforced other evidence that the three N-terminal zinc fingers of TFIIIA bind most tightly to 5S DNA. Proteolytic footprinting of TFIIIA in reconstituted 7S ribonucleoprotein particles revealed different patterns of trypsin sensitivity for TFIIIA bound to oocyte versus somatic 5S RNA. Trypsin cleaved TFIIIA between zinc fingers 3 and 4 more readily when the protein was bound to somatic 5S RNA than when it was bound to oocyte 5S RNA. A tryptic fragment of TFIIIA containing zinc fingers 4 through 7 remained tightly associated with somatic 5S RNA. Zinc fingers 4 through 7 may represent a tightly binding site for 5S RNA in the same sense that fingers 1 through 3 represent a tightly binding site for 5S DNA.

Mutations in 5S DNA and 5S RNA have different effects on the binding of Xenopus transcription factor IIIA

Biochemistry ◽  
1991 ◽  
Vol 30 (9) ◽  
pp. 2495-2500 ◽  
Author(s):  
Qimin You ◽  
Nik Veldhoen ◽  
Florence Baudin ◽  
Paul J. Romaniuk
Keyword(s):  
Transcription Factor ◽  
5S Rna ◽  
Transcription Factor Iiia ◽  
5S Dna

scholarly journals The positive transcription factor of the 5S RNA gene proteolyses during direct exchange between 5S DNA sites.

1986 ◽  
Vol 103 (3) ◽  
pp. 673-681 ◽  
Author(s):  
E B Kmiec ◽  
A Worcel
Keyword(s):  
Transcription Factor ◽  
Complex Formation ◽  
5S Rna ◽  
Specific Transcription Factor ◽  
Direct Exchange ◽  
5S Dna ◽  
Dna Complex ◽  
Vector Dna

We have examined the association, dissociation, and exchange of the 5S specific transcription factor (TFIIIA) with somatic- and oocyte-type 5S DNA. The factor associates faster with somatic than with oocyte 5S DNA, and the rate of complex formation is accelerated by vector DNA. Once formed, the TFIIIA-5S DNA complex is stable for greater than 4 h in the absence of free 5S DNA, and its dissociation is identical for somatic and for oocyte 5S DNA. In the presence of free 5S DNA, the factor transfers promptly from the complex to the free 5S DNA site. Unexpectedly, the direct exchange of factor between 5S DNA sites leads to proteolysis at the C-terminal arm of TFIIIA.

Sign in / Sign up

Export Citation Format

Share Document