Análisis de la Variación Genética Natural de la Fotomorfogénesis en Arabidopsis Thaliana
[EN] After germination, seedlings can follow two alternative development programs, photomorphogenesis or escotomorfogénesis depending on the presence or absence of light, respectively. The transition between the two programs is under strict hormonal control; thus GAs repress photomorphogenesis in da...
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| Formato: | tesis doctoral |
| Fecha de publicación: | 2016 |
| País: | España |
| Recursos: | Universitat Politècnica de València (UPV) |
| Repositorio: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia |
| Idioma: | español |
| OAI Identifier: | oai:riunet.upv.es:10251/61955 |
| Acesso em linha: | https://riunet.upv.es/handle/10251/61955 |
| Access Level: | acceso abierto |
| Palavra-chave: | Giberelinas Paclobutrazol, variación natural Fotomorfogénesis DELLA |
| Resumo: | [EN] After germination, seedlings can follow two alternative development programs, photomorphogenesis or escotomorfogénesis depending on the presence or absence of light, respectively. The transition between the two programs is under strict hormonal control; thus GAs repress photomorphogenesis in darkness. The main objective of this paper is whether this regulation has an adaptive value. We have studied the variability in 150 accessions of Arabidopsis thaliana in regulating the Photomorphogenesis by GAs and analyzed morphological characteristics that differ between the two development programs (angle between cotyledons and hypocotyl length) by selecting 7 accessions hypersensitive to GAs deficiency, 7 intermediate accessions, and 7 less sensitive to deficiency of GAs. We performed a sequence analysis of 8 genes (GID1a, GID1b, GID1c, GAI, RGA, SLY1, HY5 and PIF3) involved in the signaling of GAs in the 21 selected accessions, that has shown no clear correlation between allelic varieties and the expression of the phenotype, except the accession Bla-1, which has a truncated version of GAI. On the other hand, there has been a transcriptome analysis and QTL analysis with two accessions with different behaviors in absence of GAs, obtaining 4 new loci and 307 candidate genes that may be involved in the process. Finally, it has undertaken a screening of transcription factors in Arabidopsis that could participate in Photomorphogenesis, examining two phenotypes in darkness without GAs: the opening of apical hook after 3 days and the opening of cotyledons after 7 days. This analysis has demonstrated that these processes are highly sensitive to the activity of transcription factors, showing a similar variation found among natural populations. |
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