Trypanosoma brucei
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA290850 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR2125770.fastq.gz | Fastqsanger.gz | |||
| SRR2125780.fastq.gz | Fastqsanger.gz | |||
| SRR2125761.fastq.gz | Fastqsanger.gz | |||
| SRR2125771.fastq.gz | Fastqsanger.gz | |||
| SRR2125781_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 31 |
Similar Datasets
Project description:Small non-coding RNA biogenesis typically involves cleavage of structured precursors by RNase III-like endonucleases. However, guide RNAs that direct U-insertion/deletion mRNA editing in mitochondria of trypanosomes maintain 5â² triphosphate characteristic of transcription start site and possess U-tail indicative of 3â² processing and uridylation. Here, we identified a protein complex composed of RET1 TUTase and 3â²-5â² DSS1 exonuclease, and three additional subunits. This complex, termed mitochondrial 3â² processome (MPsome), is responsible for primary uridylation of ~800-nt gRNA precursors, their processive degradation to a mature length of 50-60 nt, and secondary U-tail addition. Both strands of gRNA gene are transcribed giving rise to sense and antisense precursors of similar size. Head-to-head hybridization of these transcripts blocks symmetrical 3â²-5â² degradation at the fixed distance from the double-stranded region. Together, our findings suggest a model in which gRNA is derived from the 5â² extremity of a primary molecule by uridylation-induced, antisense transcription-controlled exonucleolytic degradation. 1. we first sequenced guide RNA precursor (Gel-fractioned total cellular RNA 600-1500nt was used) transcripts from three replicates to study the their tail features and also validate observation of sense/antisense accumulation upon perturbation of pre-processing complex based on few cases. 2. we then sequenced mitochondrial small RNA and built a reference for small RNAs using our custom algorithm. We then took the mitochondrial small RNA data and uncovered the sense/antisense pair. 3. We then used CLIP-Seq data to investigate in vivo binding sites and, together with RNA IP-Seq data to understand what determine the relative abundance of sense and antisense pair of the duplex. 4. We used sequenced small mitochondrial RNA in different RNAi experiments (For RNAi experiments, 30-70nt RNA fraction was gel-isolated from total cellular RNAs) to understand which protein will affect the Utail length in mature small mitochondrial RNA.
2016-02-08 | E-GEOD-71292 | biostudies-arrayexpress
Project description:Small non-coding RNA biogenesis typically involves cleavage of structured precursors by RNase III-like endonucleases. However, guide RNAs that direct U-insertion/deletion mRNA editing in mitochondria of trypanosomes maintain 5′ triphosphate characteristic of transcription start site and possess U-tail indicative of 3′ processing and uridylation. Here, we identified a protein complex composed of RET1 TUTase and 3′-5′ DSS1 exonuclease, and three additional subunits. This complex, termed mitochondrial 3′ processome (MPsome), is responsible for primary uridylation of ~800-nt gRNA precursors, their processive degradation to a mature length of 50-60 nt, and secondary U-tail addition. Both strands of gRNA gene are transcribed giving rise to sense and antisense precursors of similar size. Head-to-head hybridization of these transcripts blocks symmetrical 3′-5′ degradation at the fixed distance from the double-stranded region. Together, our findings suggest a model in which gRNA is derived from the 5′ extremity of a primary molecule by uridylation-induced, antisense transcription-controlled exonucleolytic degradation.
2016-02-08 | GSE71292 | GEO
Project description:LlorénsRico2016 - Effects of cis-Encoded
antisense RNAs (asRNAs) - Case3
Three putative
effects of the asRNAs were considered in this study: in case 1,
the binding of the asRNA to the corresponding mRNA induces
degradation of the duplex. In case 2, the binding of the asRNA
to the mRNA induces degradation of the mRNA, but not of the
asRNA. In case 3 (this model), the mRNA and the asRNA bind
reversibly to form a stable duplex, preventing translation of
the mRNA. In all the three cases, binding to the ribosome
protects the mRNA from the effect of the asRNA.
This model is described in the article:
Bacterial antisense RNAs are
mainly the product of transcriptional noise.
Lloréns-Rico V, Cano J,
Kamminga T, Gil R, Latorre A, Chen WH, Bork P, Glass JI, Serrano
L, Lluch-Senar M.
Sci Adv 2016 Mar; 2(3): e1501363
Abstract:
cis-Encoded antisense RNAs (asRNAs) are widespread along
bacterial transcriptomes. However, the role of most of these
RNAs remains unknown, and there is an ongoing discussion as to
what extent these transcripts are the result of transcriptional
noise. We show, by comparative transcriptomics of 20 bacterial
species and one chloroplast, that the number of asRNAs is
exponentially dependent on the genomic AT content and that
expression of asRNA at low levels exerts little impact in terms
of energy consumption. A transcription model simulating mRNA
and asRNA production indicates that the asRNA regulatory effect
is only observed above certain expression thresholds,
substantially higher than physiological transcript levels.
These predictions were verified experimentally by
overexpressing nine different asRNAs in Mycoplasma pneumoniae.
Our results suggest that most of the antisense transcripts
found in bacteria are the consequence of transcriptional noise,
arising at spurious promoters throughout the genome.
This model is hosted on
BioModels Database
and identified by:
MODEL1511170002.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
2017-05-18 | MODEL1511170002 | BioModels
Project description:LlorénsRico2016 - Effects of cis-Encoded
antisense RNAs (asRNAs) - Case1
Three
putative effects of the asRNAs were considered in this study: in
case 1
,
the binding of the asRNA to the corresponding mRNA induces
degradation of the duplex. In case 2
(this
model)
the binding of the asRNA to the mRNA induces degradation of the
mRNA, but not of the asRNA. In case 3, the mRNA and the asRNA
bind reversibly to form a stable duplex, preventing translation
of the mRNA. In all the three cases, binding to the ribosome
protects the mRNA from the effect of the asRNA.
This model is described in the article:
Bacterial antisense RNAs are
mainly the product of transcriptional noise.
Lloréns-Rico V, Cano J,
Kamminga T, Gil R, Latorre A, Chen WH, Bork P, Glass JI, Serrano
L, Lluch-Senar M.
Sci Adv 2016 Mar; 2(3): e1501363
Abstract:
cis-Encoded antisense RNAs (asRNAs) are widespread along
bacterial transcriptomes. However, the role of most of these
RNAs remains unknown, and there is an ongoing discussion as to
what extent these transcripts are the result of transcriptional
noise. We show, by comparative transcriptomics of 20 bacterial
species and one chloroplast, that the number of asRNAs is
exponentially dependent on the genomic AT content and that
expression of asRNA at low levels exerts little impact in terms
of energy consumption. A transcription model simulating mRNA
and asRNA production indicates that the asRNA regulatory effect
is only observed above certain expression thresholds,
substantially higher than physiological transcript levels.
These predictions were verified experimentally by
overexpressing nine different asRNAs in Mycoplasma pneumoniae.
Our results suggest that most of the antisense transcripts
found in bacteria are the consequence of transcriptional noise,
arising at spurious promoters throughout the genome.
This model is hosted on
BioModels Database
and identified by:
MODEL1511170001.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
2017-05-18 | MODEL1511170001 | BioModels
Project description:LlorénsRico2016 - Effects of cis-Encoded antisense RNAs (asRNAs) - Case1
Three
putative effects of the asRNAs were considered in this study: in
case 1
(this
model)
,
the binding of the asRNA to the corresponding mRNA induces
degradation of the duplex. In case 2, the binding of the asRNA to
the mRNA induces degradation of the mRNA, but not of the asRNA.
In case 3, the mRNA and the asRNA bind reversibly to form a
stable duplex, preventing translation of the mRNA. In all the
three cases, binding to the ribosome protects the mRNA from the
effect of the asRNA.
This model is described in the article:
Bacterial antisense RNAs are
mainly the product of transcriptional noise.
Lloréns-Rico V, Cano J,
Kamminga T, Gil R, Latorre A, Chen WH, Bork P, Glass JI, Serrano
L, Lluch-Senar M.
Sci Adv 2016 Mar; 2(3): e1501363
Abstract:
cis-Encoded antisense RNAs (asRNAs) are widespread along
bacterial transcriptomes. However, the role of most of these
RNAs remains unknown, and there is an ongoing discussion as to
what extent these transcripts are the result of transcriptional
noise. We show, by comparative transcriptomics of 20 bacterial
species and one chloroplast, that the number of asRNAs is
exponentially dependent on the genomic AT content and that
expression of asRNA at low levels exerts little impact in terms
of energy consumption. A transcription model simulating mRNA
and asRNA production indicates that the asRNA regulatory effect
is only observed above certain expression thresholds,
substantially higher than physiological transcript levels.
These predictions were verified experimentally by
overexpressing nine different asRNAs in Mycoplasma pneumoniae.
Our results suggest that most of the antisense transcripts
found in bacteria are the consequence of transcriptional noise,
arising at spurious promoters throughout the genome.
This model is hosted on
BioModels Database
and identified by:
MODEL1511170000.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
2017-05-18 | MODEL1511170000 | BioModels
Project description:A tagged ectopic version of the ELAV-like protein Tb927.8.6650 of T. brucei was expressed in stable cell lines and pulled down. Co-purifying transcripts were analyzed by sequencing to identify RNAs associated with Tb927.8.6650.
2013-04-18 | GSE46160 | GEO
Project description:The canonical poly (A) polymerase PAP1 polyadenylates non-coding RNAs and is essential for snoRNA biogenesis in Trypanosoma brucei
| PRJNA385386 | ENA
Project description:Trypanosoma brucei brucei guide RNA Transcriptome or Gene expression
| PRJNA208500 | ENA
Project description:Small nucleolar RNAs controlling rRNA processing in Trypanosoma brucei
| PRJNA434647 | ENA
Project description:In Trypanosoma brucei, genes are arranged in Polycistronic Transcription Units (PTUs), which are demarcated by transcription start and stop sites. Transcription start sites are also binding sites of Origin Recognition Complex 1 (ORC1). These suggest that transcription and replication in trypanosomes must occur in highly ordered and cooperative manners. Not coincidently, our previous genetic screen, a LOss of transcription Silencing (LOS) screen, identified a T. brucei MCM-BP, which forms a complex with subunits of the replicative helicase MCM. Here, I show that TbMCM-BP is required for DNA replication and transcription. TbMCM-BP depletion causes a significant reduction of replicating cells in S phase and genome-wide impairments of replication origin activation. Moreover, levels of sense and antisense transcripts increase at boundaries of PTUs in the absence of TbMCM-BP. TbMCM-BP is also important for transcriptional repression of the specialized subtelomeric PTUs, the Bloodstream-form Expression-Sites (BESs), which house the gene of antigenic importance, VSG. In the absence of TbMCM-BP, expression of silent VSGs is elevated, silent promoter regions are derepressed, and antisense transcription increases downstream of the silent promoters. This study reveals that TbMCM-BP, a replication initiation protein, guides transcription to properly start and stop, and also helps it move in the correct direction.
2018-10-19 | GSE118232 | GEO