Characterization of novel microsatellite markers from the worldwide invasive ascidian Styela plicata
- PDF / 170,639 Bytes
- 3 Pages / 595.276 x 790.866 pts Page_size
- 17 Downloads / 166 Views
TECHNICAL NOTE
Characterization of novel microsatellite markers from the worldwide invasive ascidian Styela plicata Claudio A. Valero-Jime´nez • Rocı´o Pe´rez-Portela Susanna Lo´pez-Legentil
•
Received: 7 December 2011 / Accepted: 17 December 2011 / Published online: 25 December 2011 Ó Springer Science+Business Media B.V. 2011
Abstract Ten polymorphic microsatellites loci were isolated and characterized from the invasive ascidian Styela plicata by 454 pyrosequencing. From over a hundred potential microsatellite regions, 18 were selected for screening and 10 were retained based on amplification success and marker polymorphism in a sample of 39 individuals from Spain and the United States of America. The number of alleles per locus ranged from 3 to 10, with an average of 6.4 (±2.5 SD). None of the loci showed significant linkage disequilibrium or evidence of large allele drop out or scoring errors. Departure from Hardy– Weinberg equilibrium was observed for two loci in the Spanish population and five loci in the American population, where drastic annual shifts in population genetic structure have been observed. These markers will facilitate further studies on the genetic structure of this species at small spatial and temporal scales. Keywords Sea-squirt Tunicata Pyrosequencing Excess homozygosity Genetic structure
Ascidians are sessile marine invertebrates often found in artificial substrates such as harbors and aquaculture facilities (Lambert 2002, 2007). However, some species have spread to the surrounding natural habitat, becoming invasive and causing ecological and economic concerns (Lambert 2007). Until recently, the worldwide distribution
C. A. Valero-Jime´nez R. Pe´rez-Portela S. Lo´pez-Legentil (&) Department of Animal Biology (Invertebrates), University of Barcelona, 643 Diagonal Avenue, 08028 Barcelona, Spain e-mail: [email protected]
of the solitary ascidian Styela plicata (Lesueur, 1823) was considered restricted to harbors and man-made structures (Barros et al. 2009; Pineda et al. 2011) but recent observations have reported this species in natural habitats from Sakushima Island, Japan (Nishikawa personal comm.; Pineda et al. 2011), the Ebro Delta in Spain (Pe´rez-Portela pers. obs.), and Urca Beach, Rio de Janeiro, Brazil (Paiva pers. comm.). The success of S. plicata has been attributed to high tolerance of heavy metals (Galletly et al. 2007), the ability to cope with significant temperature and salinity fluctuations (Thiyagarajan and Qian 2003), and fast growth rates to maturity (Yamaguchi 1975). Here we used 454 pyrosequencing to isolate novel microsatellite loci in Styela plicata. Genomic DNA was extracted using the QIAampÒ DNA Mini kit (QIAGEN) to a final DNA concentration of 5 ng/ll and distributed in two physically separated lanes of a plate. Pyrosequencing was performed on a Roche Life Science GS-FLX 454 System at the Scientific-Technical Services of the University of Barcelona. A total of 159,832 reads passed quality filtering with a mode length of 330 base pairs (average 277.88 ± 1
Data Loading...
