MicroRNA (miRNAs, miRs) are a family of small noncoding RNAs that regulate gene expression by sequence-selective targeting if miRNAs, leading to translational repression or mRNA degradation. Considering that a single miRNA can target several mRNAs and the 3'UTR sequence of a single mRNA might contain several signals for miRNA recognition, at least 10-40% of human mRNAs are potential targets of microRNAs, leading to control of highly regulated biological functions. In our laboratory we have analyzed by microarray the miR-profile in erythroid precursor cells (ErPC) from normal and thalassemic patients expressing different levels of foetal haemoglobin (including patients exhibiting a HPFH phenotype). The microarray data were confirrmed by RT-PCR analysis, and allowed us to identify miR-210 as highly expressed in the erythroid precursor cells from HPFH patients. When RT-PCR was performed on mithramycin (MTH)-induced K562 cells and erythroid precursor cells, we demonstrated that miR-210is induced in time-dependent and dose-dependent fashion, together with induction of gamma-globin genes. Molecular biology studies allowed to identify raptor mRNA and TORC1 as putative miR-210 targets. As far as modulation of miR-210, peptide nucleic acids (PNAs) might be of interest. We have studies a PNA conjugated to a polyarginine peptide which (a) is efficiently internalized within target cells; (b) strongly inhibits miR-210 activity; (c) deeply alters the expression of raptor mRNA and gamma-globin genes
MicroRNA and erythroid differentiation
GAMBARI, Roberto
2011
Abstract
MicroRNA (miRNAs, miRs) are a family of small noncoding RNAs that regulate gene expression by sequence-selective targeting if miRNAs, leading to translational repression or mRNA degradation. Considering that a single miRNA can target several mRNAs and the 3'UTR sequence of a single mRNA might contain several signals for miRNA recognition, at least 10-40% of human mRNAs are potential targets of microRNAs, leading to control of highly regulated biological functions. In our laboratory we have analyzed by microarray the miR-profile in erythroid precursor cells (ErPC) from normal and thalassemic patients expressing different levels of foetal haemoglobin (including patients exhibiting a HPFH phenotype). The microarray data were confirrmed by RT-PCR analysis, and allowed us to identify miR-210 as highly expressed in the erythroid precursor cells from HPFH patients. When RT-PCR was performed on mithramycin (MTH)-induced K562 cells and erythroid precursor cells, we demonstrated that miR-210is induced in time-dependent and dose-dependent fashion, together with induction of gamma-globin genes. Molecular biology studies allowed to identify raptor mRNA and TORC1 as putative miR-210 targets. As far as modulation of miR-210, peptide nucleic acids (PNAs) might be of interest. We have studies a PNA conjugated to a polyarginine peptide which (a) is efficiently internalized within target cells; (b) strongly inhibits miR-210 activity; (c) deeply alters the expression of raptor mRNA and gamma-globin genesI documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.