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Large-scale analysis by SAGE reveals new mechanisms of v-erbA oncogene action.

Bresson C, Keime C, Faure C, Letrillard Y, Barbado M, Sanfilippo S, Benhra N, Gandrillon O, Gonin-Giraud S - BMC Genomics (2007)

Bottom Line: We then focused our study on 15 of the new v-ErbA target genes and demonstrated by real time PCR that in majority their expression was activated neither by T3, nor RA, nor during differentiation.This was unexpected based upon the previously known role of v-ErbA.This paper suggests the involvement of a wealth of new unanticipated mechanisms of v-ErbA action.

View Article: PubMed Central - HTML - PubMed

Affiliation: Université de Lyon, Lyon, F-69003, France . bresson@cgmc.univ-lyon1.fr

ABSTRACT

Background: The v-erbA oncogene, carried by the Avian Erythroblastosis Virus, derives from the c-erbAalpha proto-oncogene that encodes the nuclear receptor for triiodothyronine (T3R). v-ErbA transforms erythroid progenitors in vitro by blocking their differentiation, supposedly by interference with T3R and RAR (Retinoic Acid Receptor). However, v-ErbA target genes involved in its transforming activity still remain to be identified.

Results: By using Serial Analysis of Gene Expression (SAGE), we identified 110 genes deregulated by v-ErbA and potentially implicated in the transformation process. Bioinformatic analysis of promoter sequence and transcriptional assays point out a potential role of c-Myb in the v-ErbA effect. Furthermore, grouping of newly identified target genes by function revealed both expected (chromatin/transcription) and unexpected (protein metabolism) functions potentially deregulated by v-ErbA. We then focused our study on 15 of the new v-ErbA target genes and demonstrated by real time PCR that in majority their expression was activated neither by T3, nor RA, nor during differentiation. This was unexpected based upon the previously known role of v-ErbA.

Conclusion: This paper suggests the involvement of a wealth of new unanticipated mechanisms of v-ErbA action.

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Related in: MedlinePlus

Real time PCR validation on multiple experiments. The results of the real-time PCR quantification of genes repressed by the transforming form of v-ErbA and identified by SAGE are presented. Total RNA was extracted from the T2ECs expressing either the oncogenic form or the non-transforming form of v-erbA. A reverse transcription and real-time PCR analysis were performed to quantify the expression level of different genes. The fold repression is represented, corresponding to a decrease of mRNA accumulation in T2ECs expressing the transforming form of v-ErbA (VA) in comparison with T2ECs expressing the non-transforming form of v-ErbA (NTVA). The grey bars represent a mean of ratio calculated using three reference genes T-Complex 1, hnRNP and ATP synthase subunit B1. The hatched bar is the mean of mRNA accumulation in the five independent experiments.
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Figure 5: Real time PCR validation on multiple experiments. The results of the real-time PCR quantification of genes repressed by the transforming form of v-ErbA and identified by SAGE are presented. Total RNA was extracted from the T2ECs expressing either the oncogenic form or the non-transforming form of v-erbA. A reverse transcription and real-time PCR analysis were performed to quantify the expression level of different genes. The fold repression is represented, corresponding to a decrease of mRNA accumulation in T2ECs expressing the transforming form of v-ErbA (VA) in comparison with T2ECs expressing the non-transforming form of v-ErbA (NTVA). The grey bars represent a mean of ratio calculated using three reference genes T-Complex 1, hnRNP and ATP synthase subunit B1. The hatched bar is the mean of mRNA accumulation in the five independent experiments.

Mentions: The relative expression levels of v-ErbA target genes identified by SAGE were quantified by real-time PCR in T2ECs expressing the transforming form of v-ErbA (VA) compared to T2ECs expressing the non-transforming form of v-ErbA (NTVA) in five independent experiments. We selected 40 candidates and used the sequence of the corresponding transcripts in order to design PCR primers. The differential expression between VA and NTVA conditions has been observed for 15 of them (Figure 5). All these genes are repressed by the transforming form of v-ErbA compared to the non-transforming one. The majority of these genes are involved in protein synthesis, like ribosomal proteins (RPS3, RPS3a, RPS9, RPL13) and translation initiation and elongation factors (eIF2B2, eEF1α1).


Large-scale analysis by SAGE reveals new mechanisms of v-erbA oncogene action.

Bresson C, Keime C, Faure C, Letrillard Y, Barbado M, Sanfilippo S, Benhra N, Gandrillon O, Gonin-Giraud S - BMC Genomics (2007)

Real time PCR validation on multiple experiments. The results of the real-time PCR quantification of genes repressed by the transforming form of v-ErbA and identified by SAGE are presented. Total RNA was extracted from the T2ECs expressing either the oncogenic form or the non-transforming form of v-erbA. A reverse transcription and real-time PCR analysis were performed to quantify the expression level of different genes. The fold repression is represented, corresponding to a decrease of mRNA accumulation in T2ECs expressing the transforming form of v-ErbA (VA) in comparison with T2ECs expressing the non-transforming form of v-ErbA (NTVA). The grey bars represent a mean of ratio calculated using three reference genes T-Complex 1, hnRNP and ATP synthase subunit B1. The hatched bar is the mean of mRNA accumulation in the five independent experiments.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2194726&req=5

Figure 5: Real time PCR validation on multiple experiments. The results of the real-time PCR quantification of genes repressed by the transforming form of v-ErbA and identified by SAGE are presented. Total RNA was extracted from the T2ECs expressing either the oncogenic form or the non-transforming form of v-erbA. A reverse transcription and real-time PCR analysis were performed to quantify the expression level of different genes. The fold repression is represented, corresponding to a decrease of mRNA accumulation in T2ECs expressing the transforming form of v-ErbA (VA) in comparison with T2ECs expressing the non-transforming form of v-ErbA (NTVA). The grey bars represent a mean of ratio calculated using three reference genes T-Complex 1, hnRNP and ATP synthase subunit B1. The hatched bar is the mean of mRNA accumulation in the five independent experiments.
Mentions: The relative expression levels of v-ErbA target genes identified by SAGE were quantified by real-time PCR in T2ECs expressing the transforming form of v-ErbA (VA) compared to T2ECs expressing the non-transforming form of v-ErbA (NTVA) in five independent experiments. We selected 40 candidates and used the sequence of the corresponding transcripts in order to design PCR primers. The differential expression between VA and NTVA conditions has been observed for 15 of them (Figure 5). All these genes are repressed by the transforming form of v-ErbA compared to the non-transforming one. The majority of these genes are involved in protein synthesis, like ribosomal proteins (RPS3, RPS3a, RPS9, RPL13) and translation initiation and elongation factors (eIF2B2, eEF1α1).

Bottom Line: We then focused our study on 15 of the new v-ErbA target genes and demonstrated by real time PCR that in majority their expression was activated neither by T3, nor RA, nor during differentiation.This was unexpected based upon the previously known role of v-ErbA.This paper suggests the involvement of a wealth of new unanticipated mechanisms of v-ErbA action.

View Article: PubMed Central - HTML - PubMed

Affiliation: Université de Lyon, Lyon, F-69003, France . bresson@cgmc.univ-lyon1.fr

ABSTRACT

Background: The v-erbA oncogene, carried by the Avian Erythroblastosis Virus, derives from the c-erbAalpha proto-oncogene that encodes the nuclear receptor for triiodothyronine (T3R). v-ErbA transforms erythroid progenitors in vitro by blocking their differentiation, supposedly by interference with T3R and RAR (Retinoic Acid Receptor). However, v-ErbA target genes involved in its transforming activity still remain to be identified.

Results: By using Serial Analysis of Gene Expression (SAGE), we identified 110 genes deregulated by v-ErbA and potentially implicated in the transformation process. Bioinformatic analysis of promoter sequence and transcriptional assays point out a potential role of c-Myb in the v-ErbA effect. Furthermore, grouping of newly identified target genes by function revealed both expected (chromatin/transcription) and unexpected (protein metabolism) functions potentially deregulated by v-ErbA. We then focused our study on 15 of the new v-ErbA target genes and demonstrated by real time PCR that in majority their expression was activated neither by T3, nor RA, nor during differentiation. This was unexpected based upon the previously known role of v-ErbA.

Conclusion: This paper suggests the involvement of a wealth of new unanticipated mechanisms of v-ErbA action.

Show MeSH
Related in: MedlinePlus