INDEX
ABSTRACT I
1. INTRODUCTION
1.1 Discovery of serotonin 1
1.2 Synthesis and metabolism of serotonin 2 1.3 Serotonin distribution and function 6 1.4 Serotonin signalling: 5-HT receptors 8 1.5 Serotonin and neuropsychiatric disorders 14
1.6 Serotonin and development 17
1.7 Anatomy of serotonergic system 19
1.8 Development of the serotonergic system 24 1.9 Pet1 and serotonergic neuron heterogeneity 30 1.10 Tph2 and serotonergic system development 31 1.11 Aim of the thesis and experimental approach 33 2. MATERIAL AND METHODS
2.1 Animals 35
2.2 Genotyping 35
2.3 Generation of the Pet1/Cre targeting vector 35
2.4 Immunohistochemistry 36
2.5 X-gal chromogenic reaction 37
2.6 Preparation of riboprobes for non-radioactive
in situ hybridization 38
2.7 Non-radioactive in situ hybridization 39
2.8 Radioactive in situ hybridization 41
2.9 RNA extraction and RT-PCR analysis 43 2.10 Fluorescent cell sorting for microarray analysis 44
3. RESULTS
3.1 Generation of Pet1/Cre transgenic mouse line 45 3.2 Pet1/Cre mouse line reveals the presence of a
non-serotonergic Pet1-positive neuronal population
in the raphe nuclei 49
3.3 Pet1/Cre transgenic mouse line highlights Pet1
expression in developing pancreas and kidney 55 3.4 Effect of serotonin depletion on serotonergic
circuitry formation 64
3.5 5-HT regulates serotonergic system via a cell- and
non-cell-autonomous mechanism 74
4. DISCUSSION
4.1 Pet1/Cre transgene drives Cre-mediated recombination in serotonergic neurons within the raphe nuclei 75 4.2 Pet1/Cre transgenic line identifies a non-serotonergic
Pet1-expressing cell population within the raphe nuclei 78 4.3 Pet1/Cre transgenic line identifies new Pet1 expression
domains in the developing pancreas and kidney 80 4.4 Developmental role of serotonin on the
serotonergic circuitry formation 83
5. REFERENCES 87
6. ADDITIONAL RESEARCH ACTIVITY PERFORMED 109 6.1 Lack of brain serotonin affects postnatal development and
serotonergic neuronal circuitry formation 110 6.2 Generation of the floxedTph2 allele 142 6.3 A targeted serotonergic neuron reporter stem cell
line to model in vitro serotonergic neuron development
6.4 Genetically engineered stem cells, method of production
and uses thereof" 150
6.5 GCG triplet expansion in ARX gene in West syndrome: generation of an animal model suitable for
morpho-functional analysis 189
6.6 An epilepsy-related ARX polyalanine expansion modifies glutamatergic neurons excitability and morphology without affecting GABAergic neurons development 211
