Bringing annelid regeneration into the 21st century: advances in developing naidid worms as a model

ZATTARA, E.E.; BELY, A.E.

Santa Cruz

Congreso; 5th International Meeting of the Latin American Society; 2010

Latin American Society for Developemtal Biology

Annelid worms were among the first organisms used to experimentally investigate regeneration, the restorative process triggered in many animals by loss of a major body part. Although annelids were studied extensively during the 19th and the first half of the 20th centuries, interest in this group waned as technical limitations hampered efforts to tackle fundamental questions such as: Where do cells that make up new tissues come from?  What molecular processes initiate and control the development of new structures? The spectacular recent advances in molecular techniques and microscopy are now allowing a modern renaissance in the study of annelid regeneration. Naidid annelids, a group of small, mostly freshwater oligochaetes, provide a useful study system because of their high regenerative ability, small size, ease of culture, and transparency.  Our lab is currently developing resources for studying head and tail regeneration in this group. We are using fluorescence immunohistochemistry and confocal microscopy to reveal details of tissue morphogenesis, have developed robust methods for immobilizing live, regenerating material, allowing in vivo time-lapse photography of specimens for greater than 5 days (sufficient to observe complete regeneration), and are using a combination of cell proliferation markers, chemical inhibition, and in vivo cell tracing with lipophilic carbocyanine dyes to begin investigating the cell sources of new tissues. Efforts to elucidate the molecular mechanisms underlying naidid regeneration by gene expression analysis and gene knockdown are also ongoing and are facilitated by a transcriptome recently generated by others in our lab for one focal species.