| First Author | Hara M | Year | 2004 |
| Journal | Am J Physiol Cell Physiol | Volume | 287 |
| Issue | 4 | Pages | C932-8 |
| PubMed ID | 15163621 | Mgi Jnum | J:134788 |
| Mgi Id | MGI:3789799 | Doi | 10.1152/ajpcell.00151.2004 |
| Citation | Hara M, et al. (2004) Imaging endoplasmic reticulum calcium with a fluorescent biosensor in transgenic mice. Am J Physiol Cell Physiol 287(4):C932-8 |
| abstractText | The use of biosynthetic fluorescent sensors is an important new approach for imaging Ca(2+) in cells. Genetically encoded indicators based on green fluorescent protein, calmodulin, and fluorescence resonance energy transfer (FRET) have been utilized to measure Ca(2+) in nonmammalian transgenic organisms and provide information about the organization and regulation of Ca(2+) signaling events in vivo. However, expression of biosynthetic FRET-based Ca(2+) indicators in transgenic mammals has proven to be problematic. Here, we report transgenic expression of an endoplasmic reticulum (ER) Ca(2+) biosensor in mouse pancreas. We targeted expression of a yellow cameleon3.3er (YC3.3er) transgene with mouse insulin I promoter. YC3.3er protein expression was limited to pancreatic beta-cells within islets of Langerhans and absent in the exocrine pancreas and other tissues. Animals developed and matured normally; sensor expression was unaffected by age. Glucose tolerance in transgenic mice was also unaffected, indicating the transgenic biosensor did not impair endocrine pancreas function. ER Ca(2+) responses after administration of thapsigargin, carbachol, and glucose were measured in individual beta-cells of intact islets using confocal microscopy and confirmed the function of the biosensor. We conclude that controlling transgene transcription with a cell-specific promoter permits transgenic expression of FRET-based Ca(2+) sensors in mammals and that this approach will facilitate real-time optical imaging of signal transduction events in living tissues. |
