Bioimaging of microRNA124a-independent neuronal differentiation of human G2 neural stem cells

Journal Article

Kim, Jonghwan Lee, Seung U Kim, Dong Soo Lee, Yong Seung Lee, Hyejung Heo, Ali, B.A., Abdulaziz A Al-Khedhairy, Soonhag . 2015

• Publication Work Type: Research Article
• Magazine \ Newspaper: FEBS Open Bio,
• Volume Number: 5
• Pages: 647-655.

Publication Abstract

Evaluation of the function of microRNAs (miRNAs or miRs) through miRNA expression profiles during

neuronal differentiation plays a critical role not only in identifying unique miRNAs relevant to cellular

development but also in understanding regulatory functions of the cell-specific miRNAs in living

organisms. Here, we examined the microarray-based miRNA expression profiles of G2 cells (recently

developed human neural stem cells) and monitored the expression pattern of known neuronspecific

miR-9 and miR-124a during neuronal differentiation of G2 cells in vitro and in vivo. Of 500

miRNAs analyzed by microarray of G2 cells, the expression of 90 miRNAs was significantly increased

during doxycycline-dependent neuronal differentiation of G2 cells and about 60 miRNAs showed a

gradual enhancement of gene expression as neuronal differentiation progressed. Real-time PCR

showed that expression of endogenous mature miR-9 was continuously and gradually increased in

a pattern dependent on the period of neuronal differentiation of G2 cells while the increased expression

of neuron-specific mature miR-124a was barely observed during neurogenesis. Our recently

developed miRNA reporter imaging vectors (CMV/Gluc/3PT_miR-9 and CMV/Gluc/3PT_miR-124a)

containing Gaussia luciferase, CMV promoter and three copies of complementary nucleotides of each

corresponding miRNA showed that luciferase activity from CMV/Gluc/3PT_miR-9 was gradually

decreased both in vitro and in vivo in G2 cells induced to differentiate into neurons. However,

in vitro and in vivo bioluminescence signals for CMV/Gluc/3PT_miR-124a were not significantly different

between undifferentiated and differentiated G2 cells. Our results demonstrate that biogenesis

of neuron-specific miR-124a is not necessary for doxycycline-dependent neurogenesis of G2 cells.