Submitted to: Developmental Dynamics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/31/2004
Publication Date: 6/1/2004
Citation: Swanberg, S.E., Payne, W.S., Hunt, H.D., Dodgson, J.B., Delany, M.E. 2004. Telomerase activity and differential expression of telomerase genes and c-myc in chicken cells in vitro. Developmental Dynamics. 231:14-21. Available: www.interscience.wiley.com. Interpretive Summary: Chicken cells, capable of developing into various tissues, were grown in culture. The cells retained their ability to produce a protein named telomerase, an enzyme necessary to promote continued cell growth. This enzyme is characteristic of embryonic cells with the capability, upon stimulation, to differentiate into various tissue cell types. The cells were grown in culture for six months while retaining the telomerase enzyme activity. This information will aid academic and industry researchers involved in avian embryology and genetics.
Technical Abstract: Embryonic stem (ES) cells, undifferentiated pluripotent cells derived from an embryonic cell population, are important tools in basic and applied research. In this study we assessed telomerase activity and gene expression profiles for chicken telomerase reverse transcriptase (chTERT), chicken telomerase RNA (chTR), and c-myc in chicken embryo fibroblasts (CEFs), chicken embryonic stem (chES) cells, and DT40 cells. Our results establish that, relative to transcription levels in telomerase-negative CEFs, chTERT and chTR are up-regulated in telomerase-positive chES cells. Transcription levels of chTERT, chTR and c-myc are dramatically up-regulated in telomerase-positive DT40 cells relative to both CEFs and chES cells. These results are consistent with a model in which telomerase activity is up-regulated in proliferating embryonic stem cells requiring stable telomeres to endure multiple rounds of cell division, down-regulated in differentiated, lifespan-limited cells and up-regulated in immortalized, transformed cells where uncontrolled proliferation is correlated with c-myc dysregulation and telomerase activity.