Cover

In vivo bioluminescent imaging of a bacterial artificial chromosome transgenic rat expressing luciferase and destabilized enhanced green fluorescent protein (eGFP) under the control of the human prolactin gene regulatory regions. Pituitary and extrapituitary (abdomen, thymus, and parathymic lymph nodes; axillary/brachial lymph nodes; and mandibular lymph nodes) gene expression of luciferase is observed after ip injection of lipopolysaccharide. The short half-life of luciferase allows for the ex vivo imaging and analysis of dynamic single cell prolactin promoter activity in the pituitary (upper region), whereas destabilized eGFP allows for the cellular characterization of prolactin-expressing cells in extrapituitary sites (lower region). From the article in this issue by Semprini et al., pages 529–538.

The editors thank Dr. Ron Smith, Alcon Laboratories, Fort Worth, TX, for collaborating with the authors to create the figure on the cover.