Germ line determinants are not localized early in sea urchin development, but do accumulate in the small micromere lineage

Celina E. Juliano, Ekaterina Voronina, Christie Stack, Maryanna Aldrich, Andrew R. Cameron, Gary M. Wessel

Research output: Contribution to journalArticlepeer-review

99 Scopus citations


Two distinct modes of germ line determination are used throughout the animal kingdom: conditional-an inductive mechanism, and autonomous-an inheritance of maternal factors in early development. This study identifies homologs of germ line determinants in the sea urchin Strongylocentrotus purpuratus to examine its mechanism of germ line determination. A list of conserved germ-line associated genes from diverse organisms was assembled to search the S. purpuratus genome for homologs, and the expression patterns of these genes were examined during embryogenesis by whole mount in situ RNA hybridization and QPCR. Of the 14 genes tested, all transcripts accumulate uniformly during oogenesis and Sp-pumilio, Sp-tudor, Sp-MSY, and Sp-CPEB1 transcripts are also uniformly distributed during embryonic development. Sp-nanos2, Sp-seawi, and Sp-ovo transcripts, however, are enriched in the vegetal plate of the mesenchyme blastula stage and Sp-vasa, Sp-nanos2, Sp-seawi, and Sp-SoxE transcripts are localized in small micromere descendents at the tip of the archenteron during gastrulation and are then enriched in the left coelomic pouch of larvae. The results of this screen suggest that sea urchins conditionally specify their germ line, and support the hypothesis that this mechanism is the basal mode of germ line determination amongst deuterostomes. Furthermore, accumulation of germ line determinants selectively in small micromere descendents supports the hypothesis that these cells contribute to the germ line.

Original languageEnglish
Pages (from-to)406-415
Number of pages10
JournalDevelopmental Biology
Issue number1
StatePublished - Dec 1 2006


  • Boule
  • CPEB
  • DMRT
  • Deuterostome
  • Germ cell-less
  • Germ line
  • MORC
  • MSY
  • Mago nashi
  • Nanos
  • Ovo
  • Piwi
  • Pumilio
  • Sea urchin
  • Small micromeres
  • SoxE
  • Tudor
  • Vasa


Dive into the research topics of 'Germ line determinants are not localized early in sea urchin development, but do accumulate in the small micromere lineage'. Together they form a unique fingerprint.

Cite this