Dataset Information

Fine-tuning of human dendritic cells regulation revealed by translational profiling

ABSTRACT: Dendritic cells (DCs) are the sentinels of the mammalian immune system and they undergo a complex maturation process mediated by activation upon pathogen detection. Recent studies described the analysis of activated DCs by transcriptional profiling, but translation regulation was never taken in account. Therefore, the nature of the mRNAs being translated at various stages of DC activation was determined with the help of translational profiling, which is the sucrose gradient fractionation of polysomal-bound mRNAs combined to microarrays analysis. Total and polysomal-bound mRNA populations were compared in immature (0h) and LPS-stimulated (4h and 16h) human monocyte-derived DCs with the help of Affymetrix microarrays. Biostatistical analysis indicated that 296 mRNA molecules are translationally regulated during DC-activation. The most abundant biological process among the regulated mRNAs was protein biosynthesis, indicating the existence of a negative feedback loop regulating translation. Interestingly, a cluster of 17 ribosomal proteins were part of the regulated mRNAs, indicating that translation may be fine-tuned by particular components of the translational machinery. Our observations highlight the importance of translation regulation during the immune response, and may favour the identification of novel gene clusters or protein networks relevant for immunity. Our study also provides information on the possible absence of correlation between gene expression and real protein production in DCs.

ORGANISM(S): Homo sapiens

PROVIDER: GSE14000 | GEO | 2009/12/31

SECONDARY ACCESSION(S): PRJNA112501

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Dendritic cells (DCs) are the sentinels of the mammalian immune system and they undergo a complex maturation process mediated by activation upon pathogen detection. Recent studies described the analysis of activated DCs by transcriptional profiling, but translation regulation was never taken in account. Therefore, the nature of the mRNAs being translated at various stages of DC activation was determined with the help of translational profiling, which is the sucrose gradient fractionation of polysomal-bound mRNAs combined to microarrays analysis. Total and polysomal-bound mRNA populations were compared in immature (0h) and LPS-stimulated (4h and 16h) human monocyte-derived DCs with the help of Affymetrix microarrays. Biostatistical analysis indicated that 296 mRNA molecules are translationally regulated during DC-activation. The most abundant biological process among the regulated mRNAs was protein biosynthesis, indicating the existence of a negative feedback loop regulating translation. Interestingly, a cluster of 17 ribosomal proteins were part of the regulated mRNAs, indicating that translation may be fine-tuned by particular components of the translational machinery. Our observations highlight the importance of translation regulation during the immune response, and may favour the identification of novel gene clusters or protein networks relevant for immunity. Our study also provides information on the possible absence of correlation between gene expression and real protein production in DCs. To identify translationally regulated mRNA molecules, gene expression derived from the polysome-bound mRNAs was compared by Affymetrix microarrays analysis to the gene expression derived from unfractionated total mRNAs derived from whole-cell lysates, as recently described on several reports (Johannes 1999, Rajasekhar 2003, Bushell 2006, Lü 2006, Parent 2008). Polysomal RNA (P) and total RNA (T) were isolated from MoDCs generated from four different blood donors. Since three timepoints (0h, 4h and 16h) were chosen for each blood donor and RNA type, twenty-four RNA samples were totally analyzed by microarrays.

Project description:Microarray comparisons of polysome loading in wild-type Arabidopsis and eif3h mutant; Goal: ; To find the target mRNAs that are translationally regulated by eIF3h. BACKGROUND: The eukaryotic translation initiation factor eIF3 has multiple roles during the initiation of translation of cytoplasmic mRNAs. However, the contributions of individual subunits of eIF3 to the translation of specific mRNAs remain poorly understood. RESULTS: Working with stable reporter transgenes in Arabidopsis thaliana it was demonstrated that the h subunit of; eIF3 contributes to the efficient translation initiation of mRNAs harboring upstream open reading frames (uORFs) in their 5â leader sequence. uORFs, which can function as devices for translational regulation, are present in over 30% of Arabidopsis mRNAs, and are enriched among mRNAs for transcriptional regulators and protein modifying enzymes. Microarray comparisons of polysome loading in wild-type and eif3h mutant plants revealed that eIF3h generally helps to maintain efficient polysome loading of mRNAs harboring multiple uORFs. Independently, eIF3h also boosted polysome loading of mRNAs with long coding sequences. Moreover, the lesion in eIF3h revealed a concerted upregulation of translation for specific functional subgroups of mRNAs, including ribosomal proteins and proteins involved in photosynthesis. CONCLUSIONS: The intact eIF3h protein contributes to efficient translation initiation on 5â leader sequences harboring multiple uORFs, although mRNA features independent of uORFs were also implicated. Moreover, our data suggest that regulons of translational control can be revealed by mutations in generic translation initiation factors. Experiment Overall Design: Polysomal and non-polysomal RNA samples were isolated from 10-day-old wild-type and eif3h mutant plants. The translation state (ratio between the polysome and non-polysome, PL/NP) for each gene in the WT and in the mutant was separately established, and then the translation states between the genotype were compared.

Dataset Information

Fine-tuning of human dendritic cells regulation revealed by translational profiling

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets