TY - JOUR

T1 - MicroRNA modulation of megakaryoblast fate involves cholinergic signaling

AU - Guimaraes-Sternberg, C

AU - Meerson, A

AU - Shaked, Abraham

AU - Soreq, H

PY - 2006/5

Y1 - 2006/5

N2 - MicroRNAs (miRNAs) are abundant small regulatory RNAs with multiple roles in cell fate determination. The processes regulating cellular miRNA levels are still unclear and experimental oligonucleotide tools to readily mimic their effects are not yet available. Here, we report that thapsigargin-induced intracellular Ca++ release suppressed pre-miR-181a levels in human promegakaryotic Meg-01 cells, induced differentiation-associated nuclear endoreduplication and caspase-3 activation and replaced the acetylcholinesterase 3' splice variant AChE-S with AChE-R, AChE, PKC and PKA inhibitors all attenuated the pre-miR-181a decline and the induced differentiation. AChmiON, a synthetic 23-mer 2'-oxymethylated oligonucleotide mimicking the miR-181a sequence, blocked the calcium-induced differentiation while elevating cellular pre-miR-181a levels and inducing DNA fragmentation and cell death. Moreover, when added to RW 264.7 macrophages, AChmiON at 100 nM induced nitric oxide production with efficiency close to that of bacterial endotoxin, demonstrating physiologically relevant activities also in blood-born monocytes/macrophagcs. The stress-induced modulation of hematopoietic miR-181a levels through AChE, PKC and PKA cascade(s) suggests using miRNA mimics for diverting the fate of hematopoietic tumor cells towards differentiation and/or apoptosis. (C) 2005 Elsevier Ltd. All rights reserved.

AB - MicroRNAs (miRNAs) are abundant small regulatory RNAs with multiple roles in cell fate determination. The processes regulating cellular miRNA levels are still unclear and experimental oligonucleotide tools to readily mimic their effects are not yet available. Here, we report that thapsigargin-induced intracellular Ca++ release suppressed pre-miR-181a levels in human promegakaryotic Meg-01 cells, induced differentiation-associated nuclear endoreduplication and caspase-3 activation and replaced the acetylcholinesterase 3' splice variant AChE-S with AChE-R, AChE, PKC and PKA inhibitors all attenuated the pre-miR-181a decline and the induced differentiation. AChmiON, a synthetic 23-mer 2'-oxymethylated oligonucleotide mimicking the miR-181a sequence, blocked the calcium-induced differentiation while elevating cellular pre-miR-181a levels and inducing DNA fragmentation and cell death. Moreover, when added to RW 264.7 macrophages, AChmiON at 100 nM induced nitric oxide production with efficiency close to that of bacterial endotoxin, demonstrating physiologically relevant activities also in blood-born monocytes/macrophagcs. The stress-induced modulation of hematopoietic miR-181a levels through AChE, PKC and PKA cascade(s) suggests using miRNA mimics for diverting the fate of hematopoietic tumor cells towards differentiation and/or apoptosis. (C) 2005 Elsevier Ltd. All rights reserved.

KW - MicroRNA

KW - miR-181

KW - megakaryocytopoiesis

KW - macrophage

KW - nitric oxide

KW - differentiation

KW - hematopoiesis

KW - acctylcholinesterase

KW - calcium

KW - apoptosis

KW - oligonucleotide

KW - caspase

KW - MEDIATED TUMOR-CYTOTOXICITY

KW - TRANSCRIPTION FACTOR GATA-1

KW - NF-KAPPA-B

KW - NITRIC-OXIDE

KW - GENE-EXPRESSION

KW - CELL-LINE

KW - IFN-GAMMA

KW - IN-VITRO

KW - MEGAKARYOCYTIC DIFFERENTIATION

KW - MURINE MACROPHAGES

U2 - 10.1016/j.leukres.2005.09.005

DO - 10.1016/j.leukres.2005.09.005

M3 - Journal article

VL - 30

SP - 583

EP - 595

JO - Leukemia Research

JF - Leukemia Research

SN - 0145-2126

IS - 5

ER -