title: Cautious use of fli1a:EGFP transgenic zebrafish in vascular research.
abstract: Integration of exogenous sequence into an intact genome may cause some artificial phenotype or unspecific observations. We noticed that there is unspecific vascular expression when using fli1a:EGFP transgenic embryos for whole-mount in situ hybridization (WISH) experiments. We therefore tested whether the residual vector sequence contained in the fli1a:EGFP transgene or the integration of transgene into the genome may cause this expression 'noise' and/or deregulation of gene expression at a genome-wide level. RNA probes were synthesized using two different methods, i.e. vector-based and PCR-based. The vector-based dnmt3 probe showed unspecific vascular expression in fli1a:EGFP embryos, but not in wildtype embryos, by WISH. Moreover, we also found that compared to that in wildtype, there were alterations in gene expression at whole-genome level in the fli1a:EGFP embryos. Our finding that the vector sequence contained in the fli1a:EGFP genome causes unspecific vascular expression by WISH and the genome-wide expression profiling is altered in fli1a:EGFP embryos strongly argue that extra caution should be taken for data interpretation when using transgenics, such as fli1a:EGFP, in developmental biology studies.
authors.affiliation: State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D016477:Artifacts; D001483:Base Sequence; D001808:Blood Vessels / Q000196:embryology* / Q000378:metabolism; D015509:Developmental Biology; D004625:Embryo, Nonmammalian / Q000098:blood supply / Q000378:metabolism; D020869:Gene Expression Profiling; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism*; D017403:In Situ Hybridization / Q000592:standards*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D051789:Proto-Oncogene Protein c-fli-1 / Q000235:genetics / Q000378:metabolism*; D015347:RNA Probes / Q000235:genetics; D019076:Transgenes; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics / Q000378:metabolism
chemical_list: D051789:Proto-Oncogene Protein c-fli-1; D015347:RNA Probes; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins