표제지
ACKNOWLEDGEMENT
CONTENTS
ABBREVIATION 11
ABSTRACT 12
General background 13
1. Embryonic stem cells 13
What is a stem cell ? 13
Deriving Human Embryonic Stem cells 13
Embryonic Stem Cells 14
Characteristics of hESC 14
Applications of stem cell for medical treatment 15
2. MicroRNAs 15
The discovery of microRNAs 15
Biogenesis of miRNAs 16
miRNAs and siRNAs, what's the difference ? 17
Functional characterization of miRNAs 20
Regulation through miRNAs 21
PART Ⅰ. Cloning of Novel MicroRNAs from Human Embryonic Stem Cells 23
Ⅰ. Introduction 23
Ⅱ. Materials and methods 25
Ⅱ. 1. hESC and mESC culture 25
Ⅱ. 2. miRNA cloning and bioinformatic analysis 25
Ⅱ. 3. Northern blot analysis 28
Ⅲ. Results 29
Ⅲ. 1. miRNAs were cloned from hESC 29
Ⅳ. Discussion 33
PART Ⅱ. Identification of MicroRNAs Expressed during Mouse Testis Development 35
Ⅰ. Introduction 35
Ⅱ. Materials and methods 38
Ⅱ. 1. Preparation of gonads, testis and tissues 38
Ⅱ. 2. Total RNA isolation and Northern blot analysis 38
Ⅱ. 3. Bioinformatics 39
Ⅲ. Results 40
Ⅳ. Discussion 44
Summary 46
References 48
Summary in Korean 57
Table 1. MicroRNAs and their targets: examples of microRNAs with experimentally validated functions/targets 22
Table 2. Cloning of microRNA. 27
Table 3. MicroRNAs cloned from human embryonic stem cells(MIZ-hES1) 31
Table 4. Expression studies on mammalian microRNAs. 37
Table 5. Mouse microRNA Sequence Identified by microRNA Registry. 41
Figure 1. The current model for the biogenesis and post-transcrip tional suppression of microRNAs and small interfering RNAs. 18
Figure 2. Predicted structures of microRNA precursors. 32
Figure 3. Expression of microRNAs in developing mouse testis and ovary examined by Northern blot analysis. 42
Figure 4. Expression of microRNAs in various tissues of 2 weeks old mouse examined by northern blot analysis. 43