The role of the transcription factor klf2a in vascular biology

Introduction: The zinc-finger transcription factor Krϋppel-like factor 2 (KLF2) transduces physical forces of blood flow into molecular signals responsible for a wide range of biological responses. KLF2 maintains a healthy, quiescent endothelial phenotype. I studied the expression and function of the zebrafish KLF2 ortholog klf2a in vascular biology. Materials and Methods: Expression patterns of genes were observed using Whole- mount in situ hybridisation (WISH) technique. Relative expressions of genes were investigated using reverse transcription quantitative polymerase chain reaction (RT- qPCR). Particle imaging velocimetry (PIV) method was used to measure blood flow velocities. Blood flow in zebrafish embryos was manipulated genetically and pharmacologically. Transcription Activator-Like Effector Nucleases (TALEN) were used to generate a stable klf2a mutant line. Western blot, mass spectrometry and immunoprecipitation techniques were used in Klf2a protein studies. klf2a mutant lines were crossed with several transgenic reporter lines to study the role of klf2a in vascular development and transcription. Results: I reproduced and extended previous studies of spatial and temporal klf2a expression patterns. I confirmed that this expression is dependent on blood flow. Morpholino-mediated klf2a knockdown was used to study the roles of klf2a in regulation of other previously identified flow-dependent genes. klf2a mutants were generated and phenotyped. The mutant phenotype was compared to the one seen in klf2a MO morphants.