Research Techniques Made Simple:Lineage Tracing Mediated by

Cre-Recombinase Activity

Susanne Vorhagen, Joanna Jackow, Simona Georgina Mohor; Giel Tanghe; Luna Tanrikulu,

Claudia Skazik-Vogt; Frederik Tellkamp

Lineage Tracing…… allows us to follow cell fate decisions of stem/ progenitor cell populations and their descendants within a living organism.

… is based on the visualization of the cell lineage via a time and spatially controlled reporter gene expression in stem/progenitor cells that is passed onto their cell progeny.

… enables us to study the dynamic of proliferation, differentiation, and migration of these cells in an in vivo context during development, homeostasis, and disease.

Cre-Recombinase-MediatedReporter Gene Expression

• A cell population specific promoter can be used to control Cre-recombinase expression in the cell population of interest

• Upon Cre-recombinase expression, the stop codon is excised and leads to reporter gene expression

• Reporter genes: • fluorescent proteins or lacZ

tracing of the cell progeny

Example:Tracing of the hair follicle stem cell progeny

Hair follicle

Interfollicular epidermis

Hair folliclestem cells

Cre-mediated induction of reporter-gene expression in hair follicle stem cells

Example:Tracing of the hair follicle stem cell progeny

Hair follicle

Interfollicular epidermis

Hair folliclestem cells

Tracing of hair follicle stem cell progeny – independently of Cre-expression