National Avian Research Facility
National Avian Research Facility

Split GFP

Inducible fluorescence of the large subunit of Green Fluorescent Protein (GFP1-10)

Split GFP
Split GFP embryo transfected with a plasmid expressing GFP-11 by injection of transfection mix into the circulation at HH16-18.

Summary & Utility

In the Split GFP line the transgene is designed so that the large subunit of GFP (GFP1-10) only fluoresces when the complementary small subunit of GFP-11 is delivered to a cell. This technique was originally developed by Cabantous et al. (2005)1. GFP-11 can be delivered by incorporation in a virus as a tag of a virally encoded protein, to report on cells that are infected by the virus, or by expression of a second protein with a GFP-11 tag. Delivery of GFP-11 has been tested by fusion of GFP-11 to an influenza virus protein and an IBDV protein with promising results using chick embryo fibroblasts from Split GFP transgenic embryos (preliminary data). Further development of the use of this line is ongoing and testing other uses are encouraged, for example by electroporation of an expression construct of a tagged protein. The Split GFP line may be particularly suitable for research into the processes of infection and for understanding the development and function of neuromuscular junctions in birds.


Line origin

The Split GFP line was generated at The Roslin Institute by Professor Helen Sang’s group, Dr Adam Balic, and in collaboration with Dr Laurence Tiley. The coding sequence for GFP1-10 was inserted in a lentivector preceded by the CAG enhancer/promoter (as for the ubiquitous expression of GFP in the Roslin Green line2). The line carries a single insertion of the transgene. When the complementary small subunit of GFP-11 (16 amino acids) is supplied to the large subunit of GFP (GFP1-10, 214 amino acids), the reassembled GFP fluoresces3This line was originally funded by the BBSRC (grant number: BB/K002465/1).

To reference this line for publications please contact Professor Helen Sang.



  1. Cabantous, S., Terwilliger, T. C. & Waldo, G. S. Protein tagging and detection with engineered self-assembling fragments of green fluorescent protein. Nat. Biotechnol. 23, 102–107 (2005).
  2. McGrew, M. J. et al. Localised axial progenitor cell populations in the avian tail bud are not committed to a posterior Hox identity. Development 135, 2289–2299 (2008).
  3. Kent, K. P., Childs, W., and Boxer, S. G. Deconstructing green fluorescent protein. J. Am. Chem. Soc. 130, 9664–9665 (2008).