2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

Chair: Reinhardt Schröder
�25 Anika Lidke A 704 / 14:00
Estradiol promoted effects on the development of primordial germ cells in the
polychaete Platynereis dumerilii
Authors: Anika Lidke 1 , Nicole Rebscher 1
Affiliation: 1 Philipps Universität, spezielle Zoologie
The steroid hormon estradiol is involved in reproductive processes like
gametogenesis, estrous cycle, induction of vitellogenesis, maturation of sexual organs
or proliferation of primordial germ cells (PGCs). For a long time estrogen signaling
was considered to be vertebrate specific, unless recently an estrogen receptor was
found in the mollusk Aplysia (Thornton et al., 2003) which however was not able to
bind estradiol. Later an estradiol receptor activated by estradiol was found in the
polychaete Platynereis dumerilii (Keay and Thornton, 2009) and biochemically and
phylogenetically characterised. Since there are no data available in vivo on the
function of estrogen in this species, we examined the effect of estradiol on PGC
development in the polychaete Platynereis dumerilii. Embryos were incubated with
estradiol at different concentrations and periods and were allowed to develop until
the age of six days post fertilisation. Larvae were then fixed and numbers of PGCs
were assessed by immunohistochemistry against the Vasa protein. After treatment
with estradiol excessive PGCs were found as compared to the control group. The
effect of estradiolon the PGCs seems to be concentration dependent.
Reference:
Thornton,J.W., Need,E., and Crews,D. 2003. Resurrecting the Ancestral Steroid Receptor: Ancient
Origin of Estrogen Signaling. Science 301: 1714-1717.
�26 Beate Mittmann A 704 / 14:15
Embryonic development and staging of the cobweb spider Parasteatoda
tepidariorum C. L. KOCH, 1841 (syn.: Achaearanea tepidariorum; Araneomorphae,
Theridiidae)
Authors: Beate Mittmann 1 , Carsten Wolff 2
Affiliations: 1 Institut für Biologie III, Neurogenetik, Albert-Ludwigs-Universität
Freiburg; 2 Institut für Vergleichende Zoologie, Humboldt-Universität zu Berlin
The cobweb spider Parasteatoda tepidariorum (C. L. KOCH, 1841; syn.: Achaearanea
tepidariorum) has become an important study organism in developmental biology
and evolution as well as in genetics. Beside Cupiennius salei, it has become a
chelicerate model organism for evo-devo studies in recent years. However, a staging
system taking into account the entire development, and detailed enough to apply to
modern studies, is still required. We describe the embryonic development of P.
tepidariorum and provide a staging system which allows easy recognition of the
distinct stages using simple laboratory tools. In addition to fluorescent stainings,
schematic drawings of all stages are provided to ease stage recognition. Furthermore,
we described and filmed the cocoon production of P. tepidariorum and provide
movies of developing eggs. As the genom of P. tepidariorum is just being sequenced,
our staging will provide a useful basis for near evo-devi-studies.
49