ProxTom transgenic mice express a red fluorescent protein, tdTomato under the direction of a Prox1 promoter. Prox1 encodes a transcription factor (prospero-related homeobox 1) that is necessary for the formation and maintenance of lymphatic vessels. The tdTomato fluorescent protein can be detected in the lymphatic vessels, adult liver, lens, and dentate gyrus. Expression of Prox1-driven tdTomato is also evident in three novel sites including the neuroendocrine cells of the adrenal medulla, megakaryocytes, and platelets. With the insertion of tdTomato upstream of the Prox1 nuclear localization sequence, fluorescence is seen only in the cytoplasm of cells. These mice may be useful in applications involving diseases associated with the lymphatic system including lymphedema, filariasis, transplant rejection, obesity, and tumor metastasis. Hemizygous females are viable and fertile, but most hemizygous males are nonproductive. These mice are currently maintained by crossing to B6129SF1/J mice (Stock No. 101043) every generation to improve litter sizes.
