Report of Systematic Zoology Lab Practicum, August, 2011

28S rDNA partial sequence of Emplectonema gracile (Nemertea: Hoplonemerta: Monostilifera)

Toshio Kubotsu

Division of Biology, Department of Biological Sciences, School of Science, Hokkaido University, Sapporo 060-0810, Japan

Material and Methods
A nemertean was obtained subtidally at Oshoro Bay, Hokkaido, Japan, about 43°12′N, 140°51′E, on 13 June 2011 by Toshi Kubotsu, photographed and identified as Emplectonema gracile (Johnston, 1837) by Hiroshi Kajihara, and fixed in 99% EtOH. DNA was extracted from the posterior part of the animal using the silica method (Boom et al. 1990) with some modifications. Extracted DNA was dissolved in 30 µl of deionized water and has been preserved at –20°C. Remaining morphological voucher specimen has been deposited at the Hokkaido University Museum under the catalogue number ICHU22090277 (contact: Hiroshi Kajihara, kazi@mail.sci.hokudai.ac.jp).
      Amplification of mitochondrial cytochrome c oxidase subunit I gene (COI) using LCO1490 (5′-GGTCAACAAATCATAAAGATATTGG-3′) and HCO2198 (5′-TAAACTTCAGGGTGACCAAAAAATCA-3′) (Folmer et al. 1994) was unsuccessful.
      An about 1000-bp fragment of 28S rRNA gene was amplified by polymerase chain reaction (PCR) using LSU5 (5′-ACCCGCTGAAYTTAAGCA-3′) andLSU3(5′-TCCTGAGGGAAACTTCGG-3′) (Littlewood et al. 1994). A hot start PCR was performed by a thermal cycler, iCycler (Bio-Rad), in a 20-µl reaction volume containing 1 µl of template total DNA (approximately 10–100 ng) and 19 µl of premix made with 632-µl deionized water, 80-µl Ex Taq Buffer (TaKara Bio), 64-µl dNTP (each 25 mM), 8-µl each primer (each 10 µM), and 0.1-µl TaKara Ex Taq (5 U/µl,TaKara Bio). Thermal cycling condition comprised an initial denaturation at 95°C for 30 sec; 30 cycles of denaturation at 95°C for 30 sec, annealing at 45°C for 30 sec, and elongation at 72°C for 45°C and a final elongation at 72°C for 7 min.
      The PCR product was purified with the silica method (Boom et al. 1990). Both strands were sequenced with a BigDye® Terminator v3.1 Cycle Sequencing Kit (Applied Biosystems) following the manufacturer's protocol, using the same primer set as the initial PCR amplification. Sequencing was performed with ABI Prism 3730 DNA Analyzer (Applied Biosystems). Chromatogram and sequence data were operated with MEGA v4 software (Tamura et al. 2007).

Results
A total of 656 bp of 28S rDNA sequence was determined from Emplectonema gracile (Johnston, 1837) (see Appendix).

Taxonomy
Phylum Nemertea
Class Enopla
Subclass Hoplonemertea
Order Monostilifera
Family Emplectonematidae Bürger, 1904
Genus Emplectonema Stimpson, 1857
Emplectonema gracile (Johnston, 1837)
(Figs 1, 2)



Fig. 1. Emplectonema gracile (Johnston, 1837), ICHU22090277, enlargement of head.




Fig. 2. Emplectonema gracile (Johnston, 1837), ICHU22090277, entire animal.



References

Boom, R., Sol, C. J. A., Salimans, M. M. M., Jansen, C. L., Wertheim-van Dillen, P. M. E., and van der Noordaa, J. 1990. Rapid and simple method for purification of nucleic acids. Journal of Clinical Microbiology 28: 495–503.