Research interests:

I am an Evolutionary Biologist and currently I am working as a Postdoc in the ‘ITZ: division of ecology & evolution.

1999-2012:

 

During these years I was strongly interested in evolutionary biology of sexual reproduction in hermaphrodites. In particular, my research aimed to understand:

  • The evolution of hermaphroditic mating systems and sexual conflict: (egg trading, parental care, transition from hermaphroditism to gonochorism, benefits to be functional males: number of sperm, fitness of functional males; Schleicherová et al., in prep)
  • Sex allocation (influence of mating opportunities; Loenzi et al., 2006, Schleicherová et al., submitt.; influence of nutritional stress on sex allocation, chemical communication, Schleicherová et al., 2006, 2010; cost of sex alocation, Lorenzi et al., 2008; size-dependent sex allocation, Schleicherová et al., in prep; sex allocation in wild and lab stocks, Schleicherová et al., in press)
  • Mating behaviour (multiple mating, egg cannibalism, direct competition, Lorenzi et al., 2006; mate choice experiments based on chemical communication, Schleicherová et al., in prep)

 

Study model

Ophryotorocha diadema is a microscopic marine polychaete worm (l = 2-3 mm), it is a simultaneous hermaphrodite with external fertilization. Its mating behaviour is called egg trading.

 Ophryotrocha diadema

 

from Oct 2012:

The animal phylum Placozoa holds a key position in the metazoan tree of life. It’s simple morphology makes it look appear as the most basal metazoan known and a variety genetic evidence also points to a position as, or close to, the last common metazoan ancestor (cf. Osigus et al., 2012 for overview and references). Its simple morphology, the presence of only five differentiated somatic cell types and the smallest metazoan genome makes it an excellent focus of research. To date Trichoplax adhaerens is the only formally described species in the phylum, making the Placozoa the only monotypic phylum in the animal kingdom (e.g. Grell, 1971; Westheide and Rieger, 1996). However, recent molecular genetic and morphological studies have identified a high diversity within this phylum, hence different genera, families and orders are awaiting taxonomic description (Eitel and Schierwater, 2010; Voigt et al., 2004). Moreover, little is known about the ecology of placozoans and important questions remain to be addressed.  

I plan to develope methods that permit me to generate 50X coverage of the entire mitochondrial genome from single field-collected animals.  Furthermore, the mtDNA studies will permit me to characterize the genetic diversity within and between placozoan populations. Next, I seek to develop NGS-based whole genome sequencing (WGS) for selected clades of placozoans.  This data will be used to identify signatures of selection, population admixtures, migration, genetic bottlenecks and comparative genomic analysis.

Study model

Trichoplax adhaerens is the simplest free-living animal that represents a primitive metazoan form, small (1-2 mm) and disc-shaped – appears as a flat irregular disc, few millimeters in diameter (up to 2 mm), 10-15 microns thick. Trichoplax has only 5 somatic cell types, lacks any kind of symmetry and has no extra cellular matrix and no nerve or muscle cells – is the simplest organized animal from a morphological perspective.

 Trichoplax adherens

Current projects:

  • Identification of species and species evolution by means of genetics and the using of comparative genomics to identify traits under selection in placozoans from different oceans.
  • Bioinformatics
  • Ecological aspects of placozoans communities

 

Selected publications:

1. Lorenzi, M. C., Sella, G., Schleicherová, D. and Ramella, L. (2005): Outcrossing hermaphroditic polychaete worms adjust their sex allocation to social conditions. Journal of Evolutionary Biology, 18: 1341-1347.

2. Schleicherová D. (2005): Outcrossing hermaphroditic polychaete worms adjust their sex allocation to social conditions. Journal of Italian Society of Ecology p. 61-67. (Marchetti Award winner for the best oral presentation on the XV Meeting of the Italian Society of Ecology).

3. Schleicherová, D., Lorenzi M. C. and Sella, G. (2006): How outcrossing hermaphrodites sense the presence of conspecifics and suppress female allocation. Behavioural Ecology, 17: 1–5.

4. Lorenzi, M. C., Schleicherová, D. and Sella, G. (2006): Life history and sex allocation in the simultaneously hermaphroditic polychaete worm Ophryotrocha diadema: the role of sperm competition. Int. Comp. Biol. pp. 1-9.

5. Lorenzi M. C., Schleicherová D. and Sella G. (2008): Sex adjustments are not functionally costly in simultaneous hermaphrodites. Marine Biology, 153: 599-604.

6. Schleicherová, D., Lorenzi, M. C., Sella, G., and Nico K. Michiels. (2010):  Gender expression and group size: a test in a hermaphroditic and a gonochoric congeneric species of Ophryotrocha (Polychaeta). Journal of Experimental Biology, 213: 1586-1590.

7. Santovito, A., Cervella, P., Schleicherová, D., and Delpero, M. (2012): Genotyping of cytokine polymorphisms in a northern Ivory Coast population reveals an high frequency of heterozygote genotypes for the TNF-α -308G>A SNP. International Journal of Immunogenetics, 39: 291-5.

8. Schleicherová, D., Sella, G. and Lorenzi, M. C. (2012): Do stable environments select against phenotypic plasticity in hermaphroditic sex allocation? (Journal of Italian Zoology, in press).

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