Telomerase deficiency in a colonial ascidian after prolonged asexual propagation
Article first published online: 11 JAN 2011
Copyright © 2011 Wiley-Liss, Inc., A Wiley Company
Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
Volume 316B, Issue 4, pages 276–283, 15 June 2011
How to Cite
Sköld, H. N., Asplund, M. E., Wood, C. A. and Bishop, J. D.D. (2011), Telomerase deficiency in a colonial ascidian after prolonged asexual propagation. J. Exp. Zool., 316B: 276–283. doi: 10.1002/jez.b.21399
- Issue published online: 4 MAY 2011
- Article first published online: 11 JAN 2011
- Manuscript Accepted: 7 DEC 2010
- Manuscript Revised: 15 NOV 2010
- Manuscript Received: 14 SEP 2010
- The Swedish Research Council (VR-NT). Grant Number: 621-2005-4605
- Foundations from the Royal Swedish Academy of Sciences.
In organisms that propagate by agametic cloning, the parental body is the reproductive unit and fitness increases with clonal size, so that colonial metazoans, despite lack of experimental data, have been considered potentially immortal. Using asexual propagation rate as a measure of somatic performance, and telomerase activity and relative telomere length as molecular markers of senescence, old (7–12 years) asexual strains of a colonial ascidian, Diplosoma listerianum, were compared with their recent sexually produced progeny. We report for the first time evidence for long-term molecular senescence in asexual lineages of a metazoan, and that only passage between sexual generations provides total rejuvenation permitting indefinite propagation and growth. Thus, this colonial ascidian has not fully escaped ageing. The possibility of somatic replicative senescence also potentially helps to explain why metazoans, with the capacity for asexual propagation through agametic cloning, commonly undergo cycles of sexual reproduction in the wild. J. Exp. Zool. (Mol. Dev. Evol.) 316:276–283, 2011. © 2011 Wiley-Liss, Inc.