Characterization of Physa acuta expressed sequence tags and transcript mining following cadmium exposure
Freshwater molluscs have found strategic applications in public and veterinary health. Additionally, they have been used as bioindicator organisms towards environmental biomonitoring of polluted waters. The freshwater pulmonate, Physa acuta has been extensively studied as a potential biomarker in aquatic habitats with heavy metal, chemical, and microbial stressors. Lack of genomic resources is the bottleneck towards the study of candidate genes responsible for the unique adaptation of the mollusc to contaminated aquatic habitats. We have reported an EST survey of functionally relevant stress and defense related genes from P. acuta in our earlier study. In continuation of the same, we generated 1108 high-quality ESTs from a normalized cDNA library, pooled from the RNA isolated from the whole body tissue of CdCl2 exposed specimens of P. acuta. After clustering and assembly, we finally obtained 730 unique sequences representing 114 contigs and 616 singletons. Annotation of EST sequences revealed that 65.2, 62.8, and 35.9 % show significant homology to NCBI non-redundant database, Molluscs amino acid database, and NCBI KOG database, respectively. The functional characterization of the ESTs in Cd treated P. acuta group showed a greater proportion of signal transduction, cytoskeleton, and extracellular structure relevant genes compared with the control group. A large proportion of transcripts of cadmium treated P. acuta fell under the poorly characterized group of genes. These EST resources provide valuable information on Cd-specific transcript expression of P. acuta and could be utilized by scientists for developing new biomonitoring markers.
KeywordsPhysa acuta Cadmium EST KOG analysis Biomarker
This research was supported by Soonchunhyang University Research Funding (20130638) and the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2009-0073975).
Compliance with ethical standards
The tissue sampling for experiments was conducted in accordance with the International Guiding Principles for Biomedical Research involving animals (1985) (http://www.ncbi.nlm.nih.gov/books/NBK25438/).
Conflict of interest
The authors declare that they have no conflict of interest.
- Bhattacharyya MH, Wilson AK, Rajan SS, Jonah M (2000) Biochemical pathways in cadmium toxicity. In: Zalups RK, Koropatnick J (eds) Molecular biology and toxicology of metals. Taylor and Francis, London, pp 34–74Google Scholar
- Gagnaire B, Geffard O, Xuereb B, Margoum C, Garric J (2007) Cholinesterase activities as potential biomarkers: characterization in two freshwater snails, Potamopygus antipodarum (Mollusca, Hydrobiidae, Smith 1889) and Valvata piscinalis (Mollusca, Valvatidae, Muller 1774). Chemosphere 71:553–560CrossRefPubMedGoogle Scholar
- Jenny MJ, Ringwood AH, Lacy ER, Lewitus AJ, Kempton JW, Gross PS, Warr GW, Chapman RW (2002) Potential indicators of stress response identified by expressed sequence tag analysis of hemocytes and embryos from the American oyster, Crassostrea virginica. Mar Biotechnol 4:81–93CrossRefPubMedGoogle Scholar
- Jo YH, Baek MK, Kang SW, Lee JB, Byun IS, Choi SH, Chae SH, Kang JH, Han YS, Park HS, Lee YS (2009) Molecular cloning and expression pattern of Metallothionein gene from the left-handed shell, Physa acuta. Korean J Malacol 25:223–230Google Scholar
- Karuthapandi M, Rao DV, Xavier Innocent B (2013) Freshwater mollusc Physa acuta (Gastropoda: Pulmonata) new distributional record from Andhra Pradesh, India. Int J Life Sci Educ Res 1:54–56Google Scholar
- Lee JS, Raisuddin S (2008) Modulation of expression of oxidative stress genes of the intertidal copepod Tigriopus japonicus after exposure to environmental chemicals. In: Murakami Y, Nakayama K, Kitamura SI, Iwata H, Tanabe S (eds) Interdisciplinary studies on environmental chemistry-biological responses to chemical pollutants. TERRAPUB, Tokyo, pp 95–105Google Scholar
- Lee YS, Jo YH, Kim DS, Kim DW, Kim MY, Choi SH, Yon JO, Byun IS, Kang BR, Jeong KH, Park HS (2004) Construction of BLAST server for mollusks. Korean J Malacol 20:165–169Google Scholar
- Lopez-Doval JC, Poquet M, Munoz I (2014) Sublethal effects of the herbicide diuron on the freshwater snail Physella acuta. Limnetica 33:205–216Google Scholar
- Luoma SN, Rainbow PS (2008) Metal contamination in aquatic environments: science and lateral management. Cambridge University Press, CambridgeGoogle Scholar
- Milan M, Coppe A, Reinhardt R, Cancela LM, Leite RB, Saavedra C, Ciofi C, Chelazzi G, Patarnello T, Bortoluzzi S, Bargelloni L (2011) Transcriptome sequencing and microarray development for the Manila clam Ruditapes philippinarum: genomic tools for environmental monitoring. BMC Genome 12:234CrossRefGoogle Scholar
- Rice P, Longden I, Bleasby A (2000) Emboss: the European molecular biology open software suite. Trends Genet 16(276):277Google Scholar
- Rivetti C, Campos B, Faria M, Catala NC, Malik A, Munoz I, Tauler R, Soares AMVM, Osorio V, Perez S, Gorga M, Petrovic M, Mastroianni N, Lopez de Alda M, Masia A, Campo J, Pico Y, Guasc H, Barcelo D, Barata C (2015) Transcriptomic, biochemical and individual markers in transplanted Daphnia magna to characterize impacts in the field. Sci Total Environ 15:200–212CrossRefGoogle Scholar
- Wadaan MAM (2007) The freshwater growing snail Physa acuta: a suitable bioindicator for testing cadmium toxicity. Saudi J Biol Sci 14:185–190Google Scholar