Research Techniques Made Simple:Zebrafish as a Model System to

Study Skin Biology and Pathology

Qiaoli Li and Jouni Uitto

Department of Dermatology and Cutaneous Biology, Jefferson Medical College, and Jefferson

Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA

Zebrafish and Embryos

• Vertebrate• Has nearly the same

complement of genes as mammals

• Develop externally• Transparent• Easy breeding• Develop quickly

Zebrafish Skin Development

Reprinted with permission from Li et al. (2011) J Invest Dermatol 131:565-71

Genetic Manipulation of Zebrafish Genome

• Forward genetics Ethylnitrosourea (ENU) or random mutagenesis

• Reverse genetics Morpholino knockdown of specific gene expression

ENU MutagenesisModified from (Dahm, 2005) Encyclopedia of Molecular Cell Biology and Molecular Medicine (Meyers RA, ed) Vol. 15: Wiley-VCH, 593-626, with permission.

Modulation of Gene Expression by Morpholino

25 nt oligo

“Knockdown”

Efficiency of Morpholino Knockdown

EGFPSP6 promoter

pCS2/EGFP vector

MO1ATG

5’UTR target gene

col17a1b/EGFP RNA + col17a1b MO1col17a1b/EGFP RNA

Splice morpholino

8.5hpf

CMO2

500bp

300bp

421bp299bp

forwardabcc6b MO2

reverse

EXON 18 EXON 19

ATG morpholino

8.5hpf 8.5hpf

Reprinted with permission from Li et al. (2011) J Invest Dermatol 131:565-71

Application of Zebrafish for Skin Research

• Wound healing and skin repair• Pigmentation• Epidermal adhesion• Skin diseases• Skin immunity• Drug screening

Advantages

• A freshwater vertebrate with a complement of genes very similar to those of mammals

• Rapid development of transparent embryos, allowing visual inspection of internal organs

• Easy breeding, with a large number of embryos and larvae

• Easy manipulation of gene expression with phenotypic consequences

• A facile and cost-efficient system for large-scale screening

Limitations

• Lack of functional stratum corneum and expression of genes necessary for terminal differentiation of epidermis

• The zebrafish genome database is not complete and contains misjoins and misassemblies

• Paucity of antibodies recognizing zebrafish protein sequences