microRNA expression profiling of the developing mouse heart.
microRNAs (miRNAs) play an important role in regulating normal organ physiology             and development. Many miRNAs show spatially and temporally restricted expression             patterns during embryogenesis and organogenesis. This study aimed to characterize             the miRNA profile of the fetal mouse heart at 4 key time-points [embryonic day             (E)12.5, E14.5, E16.5 and E18.5] in its development, by performing a sequencing             by oligonucleotide ligation and detection (SOLiD) miRNA screen. The 4 time-points             were designated as groups M1 (E18.5), M2 (E16.5), M3 (E14.5) and M4 (E12.5). miRNAs             found to have consistent fold-changes of >2.0) between the 4 time-points were             selected for further analysis. Ten miRNAs (mmu-miR-23b, mmu-miR-24, mmu-miR-23a,             mmu-miR-375, mmu-miR-29a, mmu-miR-93, mmu-miR-21, mmu-miR-25, mmu-let-7b and mmu-miR-27b)             that were the most highly expressed in the 4 groups, including the percentage             >1% of total read counts, were identified. No miRNA was consistently downregulated             or upregulated. There were 16 differentially expressed miRNAs between the later             development group (M1+M2) and the early development group (M3+M4), which were             validated by quantitative real-time PCR. Several members of the let-7 miRNA cluster             (mmu-let-7a/7d/7e/7f) were upregulated in the later development group compared             with the early development group. A network analysis of the predicted targets             of mmu-let-7a/7d/7e/7f identified 5 target genes (FOXP1, TBX5, HAND1, AKT2 and             PPARGC1A), known to be involved in cardiac development. Therefore, this study             identified several miRNAs that are abundantly expressed in the developing heart,             several of which are differentially expressed in the 4 time-points studied. Findings             of this analysis may thus clarify the mechanisms of normal heart development and             provide a physiological basis for future studies on congenital heart disease.
State Key Laboratory of Reproductive Medicine, Department of Ultrasound, Nanjing Maternal and Child Health Hospital, Nanjing Medical University, Nanjing 210029, PR China.
Li
L
Cao
Li-Ping
LP
Kong
Zhang-Bin
ZB
Yu
Shu-Ping
SP
Han
Yun-Fei
YF
Bai
Jingai
J
Zhu
Xiaoshan
X
Hu
Chun
C
Zhu
Shasha
S
Zhu
Xi-Rong
XR
Guo
D000818:Animals; D016000:Cluster Analysis; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D053263:Gene Regulatory Networks; D006321:Heart / Q000033:anatomy & histology / Q000196:embryology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D038081:Organogenesis; D017422:Sequence Analysis, DNA; D059467:Transcriptome
D035683:MicroRNAs