Advertisement

The dynamics of multiple mouth formation in Fungia granulosa: possible patterning mechanisms

  • Vered Jacoby
  • Esti Kramarsky-Winter
  • Yossi Loya
  • Ofer Mokady
Part of the Developments in Hydrobiology book series (DIHY, volume 178)

We studied patterning mechanisms acting on the formation of new mouths during regeneration of wedgeshaped fragments of the solitary coral Fungia granulosa. Mouth formation dynamics was studied in fragments taken from different parts of the adult polyp. The corals were fragmented into central and peripheral fragments in relation to each polyp’s centrally positioned mouth. The study revealed that the maintenance of the original body plan and growth axis during the process of regeneration, appears to depend on the existence of the polyp’s mouth. When damage to the coral polyp includes only partial damage to the original mouth, the regeneration process is characterized by maintenance of the growth axis and body plan. By contrast, complete removal of the original mouth results in the formation of multiple mouths and is followed by a drastic change in body plan and growth axis. Some of these mouths develop later into new polyps, which eventually detach from the original coral. During the first 2–3 mo of regeneration, ‘preliminary’ mouths developed and regressed until stabilization was attained. The appearance of new mouths in fragments farther from the original mouth (peripheral fragments) preceded by a week the appearance of new mouths in fragments that were more proximal to the original mouth (central fragments). Additionally, more mouths formed in peripheral than in central fragments. We interpret the results in light of the developmental model suggested by Meinhardt for Hydra. The formation of new mouths in regenerating fragments of Fungia is explained in terms of a source density gradient field, auto-activation, and lateral inhibition exerted by the original central mouth. These effectors determine the position and timing of mouth(s) development.

Key words: morphogenetic gradients, pattern formation, regeneration, scleractinian coral, Fungia granulosa

Keywords

Lateral Inhibition Body Plan Scleractinian Coral Growth Axis Central Fragment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Vered Jacoby
    • 1
  • Esti Kramarsky-Winter
    • 2
  • Yossi Loya
    • 2
  • Ofer Mokady
    • 1
  1. 1.The Institute for Nature Conservation ResearchTel Aviv UniversityIsrael
  2. 2.The Department of ZoologyTel Aviv UniversityIsrael

Personalised recommendations