Gamete Recognition and Egg Activation in Sea Urchins

Reproductive character displacement and the genetics of gamete recognition in tropical sea urchins.

Reproductive character displacement occurs when sympatric and allopatric populations of a species differ in traits crucial to reproduction, and it is commonly thought of as a signal of selection acting to limit hybridization. Most documented cases of reproductive character displacement involve characters that are poorly understood at the genetic level, and rejecting alternative hypotheses for b...

All males are not created equal: fertility differences depend on gamete recognition polymorphisms in sea urchins.

Behaviors, morphologies, and genetic loci directly involved in reproduction have been increasingly shown to be polymorphic within populations. Explaining how such variants are maintained by selection is crucial to understanding the genetic basis of fertility differences, but direct tests of how alleles at reproductive loci affect fertility are rare. In the sea urchin genus Echinometra, the prot...

Sulfated fucans from the egg jelly of sea urchins

Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Departamento de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Caixa Postal 68041, Rio de Janeiro, RJ, 21941-590, Brazil, Centro Nacional de Ressonância Nuclear Magnética de Macromoléculas, Departamento de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de ...

Gamete Morphology of Six Species of Sea Urchins in Saipan, CNMI

• General sperm shape characterized by conical head • Eggs characterized as large spheres in vitelline membrane • Atlantic and Pacific populations’ spermatozoa show major morphological differences from each other (Landry et al. 2003) • Western Pacific species’ sperm head length measured twice that of Central Pacific (Marks et al. 2008). • Deep sea sperm head length elongated compared to shallow...

Pentamerism and Modularity in Sea Urchins