• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigating The Roles Of Micrornas In Biotic Stress Responses And Functional Characterization Of A Novel Ztl-type F-box Protein Via Virus Induced Gene Silencing

Dagdas, Yasin Fatih 01 June 2009 (has links) (PDF)
Barley and wheat are the two most important crop species in Turkey. Molecular studies for increasing crop yield of these species are very important for the economic benefits of Turkey. Powdery mildew and yellow rust are the two main pathogens, infecting barley and wheat, respectively in our country and causing a great amount of yield loss each year. Till now, classical genetics studies were performed in order to develop resistant barley and wheat cultivars, but these studies have not been succesful. Therefore, molecular plant-pathogen interactions studies are starting to become the new tool to fight against pathogens. In this thesis, two important aspects of plant microbe interactions were investigated. In the first part, the role of microRNAs (miRNAs) in powdery mildew-barley pathosysytem, and yellow rust-wheat pathosystem were studied. The expression levels of miRNAs and their putative targets were investigated via miRNA microarray analysis and qRT-PCR, respectively, in response to virulent and avirulent pathogen infections. These data were used to establish a new model for powdery mildew-barley and yellow rust-wheat pathosystems. In the second part, functional analysis of a novel F-box gene, which was a ZTL-type F-box, was performed by using Barley Stripe Mosaic Virus mediated Virus Induced Gene Silencing. This F-box gene (HvDRF) (Hordeum vulgare Disease Related F-box) was induced upon yellow rust infection and we studied its role in powdery mildew infection. The results confirmed HvDRF as a positive regulator of race specific immunity and enlarged the roles of ZTL-type F-box proteins to biotic stress responses.
2

Micro RNA-Mediated regulation of the full-length and truncated isoforms of human neurotrophic tyrosine kinase receptor type 3 (NTRK 3)

Guidi, Mònica 13 January 2009 (has links)
Neurotrophins and their receptors are key molecules in the development of thenervous system. Neurotrophin-3 binds preferentially to its high-affinity receptorNTRK3, which exists in two major isoforms in humans, the full-length kinaseactiveform (150 kDa) and a truncated non-catalytic form (50 kDa). The twovariants show different 3'UTR regions, indicating that they might be differentiallyregulated at the post-transcriptional level. In this work we explore howmicroRNAs take part in the regulation of full-length and truncated NTRK3,demonstrating that the two isoforms are targeted by different sets of microRNAs.We analyze the physiological consequences of the overexpression of some of theregulating microRNAs in human neuroblastoma cells. Finally, we providepreliminary evidence for a possible involvement of miR-124 - a microRNA with noputative target site in either NTRK3 isoform - in the control of the alternativespicing of NTRK3 through the downregulation of the splicing repressor PTBP1. / Las neurotrofinas y sus receptores constituyen una familia de factores crucialespara el desarrollo del sistema nervioso. La neurotrofina 3 ejerce su funciónprincipalmente a través de una unión de gran afinidad al receptor NTRK3, del cualse conocen dos isoformas principales, una larga de 150KDa con actividad de tipotirosina kinasa y una truncada de 50KDa sin dicha actividad. Estas dos isoformasno comparten la misma región 3'UTR, lo que sugiere la existencia de unaregulación postranscripcional diferente. En el presente trabajo se ha exploradocomo los microRNAs intervienen en la regulación de NTRK3, demostrando que lasdos isoformas son reguladas por diferentes miRNAs. Se han analizado lasconsecuencias fisiológicas de la sobrexpresión de dichos microRNAs utilizandocélulas de neuroblastoma. Finalmente, se ha estudiado la posible implicación delmicroRNA miR-124 en el control del splicing alternativo de NTRK3 a través de laregulación de represor de splicing PTBP1.

Page generated in 0.0511 seconds