scholarly journals Differential expression of oocyte-type class III genes with fraction TFIIIC from immature or mature oocytes.

1992 ◽  
Vol 12 (3) ◽  
pp. 946-953 ◽  
Author(s):  
W F Reynolds ◽  
D L Johnson
Keyword(s):  
Differential Expression ◽  
Developmental Regulation ◽  
Mature Oocyte ◽  
Class Iii ◽  
Developmentally Regulated ◽  
Somatic Tissues ◽  
Class Iii Genes ◽  
Transcription Complexes ◽  
Dna Affinity Chromatography

The Xenopus OAX genes can be expressed in oocytes but are virtually inactive in somatic tissues. The tRNA(Met1) (tMET) genes also appear to be developmentally regulated. We have examined the reason for the differential expression of these class III genes. Analysis of the transcriptional activities of extracts derived from immature and mature oocytes revealed that the developmental regulation of these genes can be reproduced in vitro. We have partially purified the required transcription factors B and C from these extracts to ascertain the components responsible for this differential activity. The immature oocyte C fraction activates the tMET and OAX genes when reconstituted with either the immature or mature oocyte-derived B fraction. In contrast, the mature oocyte C fraction fails to activate these genes regardless of which B fraction is used. Both C fractions activated the somatic 5S gene. Purification of the oocyte C fractions by phosphocellulose or B box DNA affinity chromatography failed to separate additional activities responsible for the differential expression of OAX or tMET. By using template exclusion assays, the inability of the mature oocyte C fraction to activate transcription was correlated with an inability to form stable transcription complexes with the tMET or OAX gene.

Differential expression of oocyte-type class III genes with fraction TFIIIC from immature or mature oocytes

1992 ◽  
Vol 12 (3) ◽  
pp. 946-953
Author(s):  
W F Reynolds ◽  
D L Johnson
Keyword(s):  
Differential Expression ◽  
Developmental Regulation ◽  
Mature Oocyte ◽  
Class Iii ◽  
Developmentally Regulated ◽  
Somatic Tissues ◽  
Class Iii Genes ◽  
Transcription Complexes ◽  
Dna Affinity Chromatography

The Xenopus OAX genes can be expressed in oocytes but are virtually inactive in somatic tissues. The tRNA(Met1) (tMET) genes also appear to be developmentally regulated. We have examined the reason for the differential expression of these class III genes. Analysis of the transcriptional activities of extracts derived from immature and mature oocytes revealed that the developmental regulation of these genes can be reproduced in vitro. We have partially purified the required transcription factors B and C from these extracts to ascertain the components responsible for this differential activity. The immature oocyte C fraction activates the tMET and OAX genes when reconstituted with either the immature or mature oocyte-derived B fraction. In contrast, the mature oocyte C fraction fails to activate these genes regardless of which B fraction is used. Both C fractions activated the somatic 5S gene. Purification of the oocyte C fractions by phosphocellulose or B box DNA affinity chromatography failed to separate additional activities responsible for the differential expression of OAX or tMET. By using template exclusion assays, the inability of the mature oocyte C fraction to activate transcription was correlated with an inability to form stable transcription complexes with the tMET or OAX gene.

Developmental regulation of a novel repetitive protein of Trypanosoma brucei

1987 ◽  
Vol 7 (8) ◽  
pp. 2838-2844
Author(s):  
M R Mowatt ◽  
C E Clayton
Keyword(s):  
Trypanosoma Brucei ◽  
Tandem Repeats ◽  
Signal Sequence ◽  
Developmental Regulation ◽  
Developmentally Regulated ◽  
Hydrophobic Domain ◽  
Reading Frame ◽  
Amino Terminal ◽  
Membrane Bound

Trypanosoma brucei undergoes many morphological and biochemical changes during transformation from the bloodstream trypomastigote to the insect procyclic trypomastigote form. We cloned and determined the complete nucleotide sequence of a developmentally regulated cDNA. The corresponding mRNA was abundant in in vitro-cultivated procyclics but absent in bloodstream forms. The trypanosome genome contains eight genes homologous to this cDNA, arranged as four unlinked pairs of tandem repeats. The longest open reading frame of the cDNA predicts a protein of 15 kilodaltons, the central portion of which consists of 29 tandem glutamate-proline dipeptides. The repetitive region is preceded by an amino-terminal signal sequence and followed by a hydrophobic domain that could serve as a membrane anchor; the mRNA was found on membrane-bound polyribosomes. These results suggest that the protein is membrane associated.

scholarly journals Developmental Regulation of Transcription ofwhiE, a Locus Specifying the Polyketide Spore Pigment in Streptomyces coelicolor A3(2)

1998 ◽  
Vol 180 (9) ◽  
pp. 2515-2521 ◽  
Author(s):  
Gabriella H. Kelemen ◽  
Paul Brian ◽  
Klas Flärdh ◽  
Leony Chamberlin ◽  
Keith F. Chater ◽  
...  
Keyword(s):  
Biosynthetic Pathway ◽  
Developmental Regulation ◽  
Streptomyces Coelicolor ◽  
Colony Development ◽  
Regulation Of Transcription ◽  
Wild Type ◽  
Developmentally Regulated ◽  
Complex Locus ◽  
Spore Pigment

ABSTRACT whiE is a complex locus that specifies the polyketide spore pigment in Streptomyces coelicolor A3(2). Two divergently oriented promoters, whiEP1 andwhiEP2, were identified in the whiE gene cluster, and their activities were analyzed during colony development in wild-type and sporulation-deficient strains. Both promoters were developmentally regulated; whiEP1 and whiEP2transcripts were detected transiently at approximately the time when sporulation septa were observed in the aerial hyphae, and transcription from both promoters depended on each of the six known “early”whi genes required for sporulation septum formation (whiA, -B, -G, -H, -I, and -J). Mutation of the late sporulation-specific sigma factor gene, sigF, had no effect on the activity of whiEP1 but blocked transcription fromwhiEP2. However, ςF-containing holoenzyme was not sufficient to direct transcription of whiEP2 in vitro. The whiEP2 promoter controls expression of whiEORFVIII, encoding a putative flavin adenine dinucleotide-dependent hydroxylase that catalyzes a late tailoring step in the spore pigment biosynthetic pathway. Disruption of whiE ORFVIII causes a change in spore color, from grey to greenish (T.-W. Yu and D. A. Hopwood, Microbiology 141:2779–2791, 1995). Consistent with these observations, construction of a sigF null mutant ofS. coelicolor M145 caused the same change in spore color, showing that disruption of sigF in S. coelicolor changes the nature of the spore pigment rather than preventing its synthesis altogether.

scholarly journals Developmental regulation of edited CYb and COIII mitochondrial mRNAs is achieved by distinct mechanisms in Trypanosoma brucei

2020 ◽  
Vol 48 (15) ◽  
pp. 8704-8723
Author(s):  
Joseph T Smith Jr. ◽  
Eva Doleželová ◽  
Brianna Tylec ◽  
Jonathan E Bard ◽  
Runpu Chen ◽  
...  
Keyword(s):  
Life Cycle ◽  
Trypanosoma Brucei ◽  
High Throughput Sequencing ◽  
Environmental Changes ◽  
Developmental Regulation ◽  
Complex Life Cycle ◽  
Mrna Levels ◽  
Developmentally Regulated ◽  
Life Cycle Stages

Abstract Trypanosoma brucei is a parasitic protozoan that undergoes a complex life cycle involving insect and mammalian hosts that present dramatically different nutritional environments. Mitochondrial metabolism and gene expression are highly regulated to accommodate these environmental changes, including regulation of mRNAs that require extensive uridine insertion/deletion (U-indel) editing for their maturation. Here, we use high throughput sequencing and a method for promoting life cycle changes in vitro to assess the mechanisms and timing of developmentally regulated edited mRNA expression. We show that edited CYb mRNA is downregulated in mammalian bloodstream forms (BSF) at the level of editing initiation and/or edited mRNA stability. In contrast, edited COIII mRNAs are depleted in BSF by inhibition of editing progression. We identify cell line-specific differences in the mechanisms abrogating COIII mRNA editing, including the possible utilization of terminator gRNAs that preclude the 3′ to 5′ progression of editing. By examining the developmental timing of altered mitochondrial mRNA levels, we also reveal transcript-specific developmental checkpoints in epimastigote (EMF), metacyclic (MCF), and BSF. These studies represent the first analysis of the mechanisms governing edited mRNA levels during T. brucei development and the first to interrogate U-indel editing in EMF and MCF life cycle stages.

TFIIIR is an isoleucine tRNA

1994 ◽  
Vol 14 (6) ◽  
pp. 3588-3595
Author(s):  
H M Dunstan ◽  
L S Young ◽  
K U Sprague
Keyword(s):  
Transcription Factors ◽  
Rna Polymerase ◽  
Rna Polymerase Iii ◽  
Silk Gland ◽  
Class Iii ◽  
Nuclear Extracts ◽  
Hybrid Selection ◽  
Class Iii Genes ◽  
Selection Of

Promoter-specific transcription by silkworm RNA polymerase III is dependent on several transcription factors (TFs) in addition to the polymerase itself. The activities present in silk gland nuclear extracts that are necessary to reconstitute transcription from class III genes in vitro have been resolved into several partially purified components. These include TFIIIR, which is unusual because it is composed of RNA. Here, we identify the RNA that provides TFIIIR activity as silkworm tRNA(IleIAU). This conclusion is based on copurification of tRNA(IleIAU) with TFIIIR activity, TFIIIR activity in synthetic tRNA(Ile), and hybrid selection of TFIIIR activity by antisense tRNA(IleIAU). We have tested the ability of a variety of other tRNAs to stimulate transcription and find that TFIIIR activity is highly specific to silkworm tRNA(IleIAU).

scholarly journals SigB-Dependent In Vitro Transcription of prfA and Some Newly Identified Genes of Listeria monocytogenes Whose Expression Is Affected by PrfA In Vivo

2005 ◽  
Vol 187 (2) ◽  
pp. 800-804 ◽  
Author(s):  
Marcus Rauch ◽  
Qin Luo ◽  
Stefanie Müller-Altrock ◽  
Werner Goebel
Keyword(s):  
Gene Expression ◽  
Listeria Monocytogenes ◽  
Transcription Initiation ◽  
In Vitro Transcription ◽  
Direct Link ◽  
Class Iii ◽  
New Genes ◽  
Class Iii Genes

ABSTRACT Recent studies have identified several new genes in Listeria monocytogenes which are positively or negatively affected by PrfA and grouped into three classes (E. Milohanic et al., Mol. Microbiol. 47:1613-1625, 2003). In vitro transcription performed with promoters of some class III genes showed strict SigB-dependent but PrfA-independent transcription initiation. Transcription starting at the prfA promoter PprfA2 was also optimal with SigB-loaded RNA polymerase, suggesting a direct link between SigB- and PrfA-dependent gene expression.

scholarly journals A Subunit of Yeast TFIIIC Participates in the Recruitment of TATA-Binding Protein

1999 ◽  
Vol 19 (12) ◽  
pp. 8042-8051 ◽  
Author(s):  
Eric Deprez ◽  
Rosalía Arrebola ◽  
Christine Conesa ◽  
André Sentenac
Keyword(s):  
Essential Gene ◽  
Binding Protein ◽  
Direct Interaction ◽  
Tata Binding Protein ◽  
Initiation Factor ◽  
Trna Genes ◽  
Class Iii ◽  
A Subunit ◽  
Class Iii Genes

ABSTRACT TFIIIC plays a key role in nucleating the assembly of the initiation factor TFIIIB on class III genes. We have characterized an essential gene, TFC8, encoding the 60-kDa polypeptide, τ60, present in affinity-purified TFIIIC. Hemagglutinin-tagged variants of τ60 were found to be part of TFIIIC-tDNA complexes and to reside at least in part in the downstream DNA-binding domain τB. Unexpectedly, the thermosensitive phenotype of N-terminally tagged τ60 was suppressed by overexpression of τ95, which belongs to the τA domain, and by two TFIIIB components, TATA-binding protein (TBP) and B"/TFIIIB90 (but not by TFIIIB70). Mutant TFIIIC was deficient in the activation of certain tRNA genes in vitro, and the transcription defect was selectively alleviated by increasing TBP concentration. Coimmunoprecipitation experiments support a direct interaction between TBP and τ60. It is suggested that τ60 links τA and τB domains and participates in TFIIIB assembly via its interaction with TBP.

scholarly journals Developmental regulation of a novel repetitive protein of Trypanosoma brucei.

1987 ◽  
Vol 7 (8) ◽  
pp. 2838-2844 ◽  
Author(s):  
M R Mowatt ◽  
C E Clayton
Keyword(s):  
Trypanosoma Brucei ◽  
Tandem Repeats ◽  
Signal Sequence ◽  
Developmental Regulation ◽  
Developmentally Regulated ◽  
Hydrophobic Domain ◽  
Reading Frame ◽  
Amino Terminal ◽  
Membrane Bound

Trypanosoma brucei undergoes many morphological and biochemical changes during transformation from the bloodstream trypomastigote to the insect procyclic trypomastigote form. We cloned and determined the complete nucleotide sequence of a developmentally regulated cDNA. The corresponding mRNA was abundant in in vitro-cultivated procyclics but absent in bloodstream forms. The trypanosome genome contains eight genes homologous to this cDNA, arranged as four unlinked pairs of tandem repeats. The longest open reading frame of the cDNA predicts a protein of 15 kilodaltons, the central portion of which consists of 29 tandem glutamate-proline dipeptides. The repetitive region is preceded by an amino-terminal signal sequence and followed by a hydrophobic domain that could serve as a membrane anchor; the mRNA was found on membrane-bound polyribosomes. These results suggest that the protein is membrane associated.

scholarly journals TFIIIR is an isoleucine tRNA.

1994 ◽  
Vol 14 (6) ◽  
pp. 3588-3595 ◽  
Author(s):  
H M Dunstan ◽  
L S Young ◽  
K U Sprague
Keyword(s):  
Transcription Factors ◽  
Rna Polymerase ◽  
Rna Polymerase Iii ◽  
Silk Gland ◽  
Class Iii ◽  
Nuclear Extracts ◽  
Hybrid Selection ◽  
Class Iii Genes ◽  
Selection Of

Promoter-specific transcription by silkworm RNA polymerase III is dependent on several transcription factors (TFs) in addition to the polymerase itself. The activities present in silk gland nuclear extracts that are necessary to reconstitute transcription from class III genes in vitro have been resolved into several partially purified components. These include TFIIIR, which is unusual because it is composed of RNA. Here, we identify the RNA that provides TFIIIR activity as silkworm tRNA(IleIAU). This conclusion is based on copurification of tRNA(IleIAU) with TFIIIR activity, TFIIIR activity in synthetic tRNA(Ile), and hybrid selection of TFIIIR activity by antisense tRNA(IleIAU). We have tested the ability of a variety of other tRNAs to stimulate transcription and find that TFIIIR activity is highly specific to silkworm tRNA(IleIAU).

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