ارزیابی ژن MHC-class IIα درماهی آزاد دریای خزر (Salmo trutta caspius) به روش SSCP

نویسندگان

1 گروه تکثیر و پرورش آبزیان، دانشکده منابع طبیعی و علوم دریایی، دانشگاه تربیت مدرس، صندوق پستی: 46414-356

2 گروه ژنتیک، دانشکده علوم زیستی، دانشگاه تربیت مدرس، صندوق پستی: 175-14115

چکیده

مولکول‌ های MHC در مهره‌ داران نقش‌ مهمی در عملکردسیستم ایمنی اکتسابی داشته و ارزیابی اثرات انتخاب طبیعی و رانش ژنی بر تنوع ژنوم MHC گونه‌ های مختلف بسیار حائز اهمیت می‌ باشد. در این مطالعه تنوع ژنوم MHCگونه بومی و در معرض انقراض ماهی آزاد دریای خزر (Salmo trutta caspius) که مورد حمایت برنامه ‌های بازسازی ذخایر می‌ باشد، مورد بررسی قرار گرفت. ازاین ‌رو تنوع جایگاه DAA ژن MHC کلاس αII در 50 نمونه ماهی آزاد دریای خزر با استفاده از روش SSCP بررسی شد. نتایج تحقیق نشان می ‌دهد که این ژن حداقل واجد 15 الل می‌ باشد که الل‌ های MHCScCa-DAA*03 و MHCScCa-DAA*10 دارای بیش ‌ترین فراوانی می ‌باشند. هم‌ چنین هتروزایگوسیتی مشاهده شده (HO)، مورد انتظار (He) و شاخص شانون به ‌ترتیب برابر 0/82،0/80 و 2/037 می‌ باشد. در جمع ‌بندی باید بیان کرد، علی‌رغم تنوع بالای ژنوم MHC در ماهی آزاد دریای خزر، ولی با توجه به وضعیت حفاظتی در حال انقراض و دستکاری‌ های انسانی، بسیاری از الل‌ هایی که فراوانی پایین دارند در خطر از دست رفتن می‌ باشند. ازاین ‌رو توجه به حفظ تنوع این ژنوم طی برنامه‌ های بازسازی ذخایر ماهی آزاد دریای خزر حائز اهمیت می‌ باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Analysis of MHC-classIIα gene of Caspian trout (Salmo trutta caspius)by using single strand conformation polymorphism (SSCP) method

نویسندگان [English]

  • Kaveh khosraviani 1
  • Mohammad Reza Kalbassi 1
  • Majid Sadeghizadeh 2
1 Faculty of Marine Sciences, Tarbiat Modares University
2 3- Faculty of Biological Sciences, Tarbiat Modares University, P.O.Box: 175-14115
چکیده [English]

MHC molecules have many important functions related to adaptive immune system in vertebrates andassessment of effects of natural selection and genetic drift on MHC genes diversity of different species are very important. In this study, the MHC genes diversity of native and endangered Caspian trout (Salmotruttacaspius) fishesthat is supported by restocking programs, were investigated. Hence, DAA locus of MHC class-IIα gene became analysis in 50 samples of Caspian trout fishes by SSCP method. Results indicated this gene has at least 15 alleles that MHCScCa-DAA*03 and MHCScCa-DAA*10 alleles have the most frequency. Also, observed heterozygosity (Ho), expected heterozygosity (He) and Shannon index equal to 0.80, 0.82 and 2.037, respectively. In conclusion it must be mentioned, althogh MHC genome of Caspian trout has high allelic diversity, but according to endangered conservational state of this species and human impacts, most of low frequency alleles are in risk of allelic lost. Therefore, the conservation of this genome pool during Caspian trout restocking programs is very critical issue.

کلیدواژه‌ها [English]

  • Caspian trout
  • MHC genes
  • SSCP
  • genetic diversity
  1. Allendorf, F.W. and Luikart, G., .7002 Conservation and the genetics of populations, Mammalia. Blackwell, Malden, MA. 642 p.
  2. Bassam, B.J. and Caetano-Anollés,G., 1993. Silver staining of DNA in polyacrylamide gels. Appl Biochem Biotechnol Enzym Eng Biotechnol. Vol. 42, No. 2, pp: 181-188. 
  3. Beacham, T.D.; Lapointe, M.; Candy, J.R.; 

    McIntosh, B.; MacConnachie, C.; Tabata, 

    A. and Withler,R.E.,2004. Stock identification of Fraser River sockeye salmon using microsatellites and major histocompatibility complex variation. Trans Am Fish Soc. Vol. 133, No. 5, pp: 1117-1137.
  4. Bernatchez, L., 2001. The evolutionary history of brown trout (Salmo trutta L.) inferred from phylogeographic, nested clade, and mismatch analyses of mitochondrial DNA variation. Evolution. Vol. 55, No. 2, pp: 351– 379.
  5. Bernatchez, L. and Landry, C., 2003. MHC studies in nonmodel vertebrates: what have we learned about natural selection in 15 years? J Evol Biol. Vol. 16, No.3, pp: 363-377.
  6. Consuegra, S.; Megens, H.J.; Schaschl, H.; Leon, K.; Stet, R. and Jordan, W.C., 2005. Rapid evolution of the MHC class I locus results in different allelic compositions in recently diverged populations of Atlantic salmon. Mol Biol Evol. Vol. 22, No. 4, pp: 1095–1106.
  7. Dionne, M.; Miller, K.M.; Dodson, J.J. and Bernatchez, L., 2009. MHC standing genetic variation and pathogen resistance in wild Atlantic salmon. Phil Trans Biol Sci. Vol. 364, No. 1523, pp: 1555-1565.
  8. Frankham, R.; Ballou, J.D. and Briscoe, D.A., 2002. Introduction to Conservation Genetics, Cambridge University Press. Cambridge, UK. 617 p.
  9. Gómez, D.; Conejeros, P. and Marshall, S.H., 2010. MHC evolution in three salmonid species: a comparison between class II alpha and beta genes. Immunogenetics. Vol. 62, No. 8, pp: 531-542.
  10. Hedrick, P.W., 1994. Evolutionary genetics of the major histocompatibilitycomplex. Am Nat. Vol. 143, pp: 945–964.
  11. Hedrick, P.W.; Parker, K.M.; Miller, E.L. andMiller,P.S.,1999. Major Histocompatibility Complex Variation in the Endangered Przewalski’s Horse. Genetics. Vol. 152, No. 4, pp: 1701-1710.
  12. Hughes, A.L., 1991. MHC polymorphism and the design of captive breeding programs. Conservation Biology. Vol. 5, No. 2, pp: 249-251.
  13. IranFisheries. 2010. Annualy statistical report in Iran Fisheries Organization. Available at : www.Iranfisheries.com.  
  14. IUCN. 2012. The IUCN Red List of Threatened Species. Version 2012.2. http://www.iucnredlist.org.
  15. Karaiskou, N.; Moran, P.; Georgitsakis, G.; Abatzopoulos, T.J. and Triantafyllidis, A., 2010. High allelic variation of MHC class II alpha antigen and the role of selection in wild and cultured Sparus aurata populations. Hydrobiologia. Vol. 638, No. 1, pp: 11-20.
  16. Kheyrandish, A.; Abdoli, A.; Mostafavi, H.; Niksirat, H.; Naderi, M. and Vatandoost, S., 2010. Age and growth of brown trout (Salmo trutta) in six rivers of the Southern part of Caspian basin. Am J Anim Vet Sci. Vol. 5, pp: 8–21.
  17. Kiabi, B.H.; Abdoli, A. and Naderi, M., 1999. Status of the fish fauna in the South Caspian Basin of Iran. Zool Middle East. Vol. 18, No. 1, pp: 7140-7147.
  18. Klein, J.; Bontrop, R.E.; Dawkins, R.L.; Erlich, H.A.; Gyllensten, U.B.; Heise, E.R.; Jones, P.P.; Parham, P..; Wakeland, E.K. and Watkins, D.I., 1990. Nomenclature for the major histocompatibility complexes of different species: a proposal. Immunogenetics. Vol. 31, pp: 217–219.
  19. Klein, J., 1986. Natural History of the Major Histocompatibility Complex. New York, Wiley. 775 p.
  20. Landry, C. and Bernatchez, L., 2001. Comparative analysis of population structure across environments and geographical scales at major histocompatibility complex and microsatellite loci in Atlantic salmon (Salmo salar). Mol Ecol. Vol. 10, No. 10, pp: 2525– 2539.
  21. Langefors, A.; Von Schantz, T. and Widegren, B. 1998. Allelic variation of MHC class II in Atlantic salmon; a population genetic analysis. Heredity. Vol. 80, No. 5, pp: 568–575.
  22. Maruyama, T. and Nei, M., 1981. Genetic variability maintained by mutation and overdominant selection in finite populations. Genetics. Vol. 98, No. 2, pp:  441-459.
  23. Mccairns, R.S.; Bourget, S.and Bernatchez, L., 2011. Putative causes and consequences of MHC variation within and between locally adapted stickleback demes. Mol Ecol. Vol. 20, No. 3, pp: 486-502.
  24. Miller, K.M.; Winton, J.R.; Schulze, A.D.; Purcell, M.K. and Ming, T.J., 2004. Major histocompatibility complex loci are associated with susceptibility of Atlantic salmon to infectious hematopoietic necrosis virus. Environ Biol Fish. vol. 69, No. 1-4, pp: 307316.
  25. Miller, K.M. and Withler, R.E., 1996. The salmonid class I MHC: limited diversity in a primitive teleost. Immunological reviews. Vol. 166, No. 1, pp: 279-.392
  26. Neff, B.D. and Pitcher, T.E., 2005. Genetic quality and sexual selection: an integrated framework for good genes and compatible genes. Mol Ecol. Vol. 14, No. 1, pp: 19-.83
  27. Niksirat, H. and Abdoli, A., 2009. On the status of the critically endangered Caspian brown trout, Salmo trutta caspius, during recent decades in the southern Caspian Sea basin. Zool Middle East. Vol. 46, No. 1, pp: 7140-7149.
  28. Peakall, R. and Smouse, P.E., 6002. GENALEX 6: genetic analysis in Excel. Population genetic software for teaching and research. Mol Ecol. Vol. 6, No. 1, pp: 288-295.
  29. Rammensee, H.G., 1995. Chemistry of peptides associated with MHC class I and class II molecules. Curr Opin Immunol. Vol. 7, No. 1, pp: 85-96.
  30. Shirangi,S.A.;Kalbassi,M.R.and DorafshanS.,2011. Microsatellite Polymorphism Reveals Low Genetic Differentiation between fall and Spring Migratory Forms of Endangered Caspian Trout, salmotruttacaspius. Caspian Journal of Environmental Sciences. Vol. 9, pp: 9-16. 
  31. Shum, B.; Guethlein, L.; Flodin, L.; Adkison, M.; Hedrick, R.; Nehring, R.; Stet, R.; Secombes, C. and Parham, P., 2001. Modes of salmonid MHC Class I and II evolution differ from the primate paradigm 1. J Immunol. Vol. 166, No. 5, pp: 3297–3308.
  32. Sommer, S.,2005. The importance of immune gene variability (MHC) in evolutionary ecology and conservation. Front Zool. Vol. 2, No. 1, 16 p.
  33. Sunnucks, P.A.C.C.; Wilson, A.C.C.; Beheregaray, L.B.; Zenger, K.; French, J. and Taylor, A., C. 2001. SSCP is not so difficult: the application and utility of singlestranded conformation polymorphism in evolutionary biology and molecular ecology. Mol Ecol. Vol. 9, No. 11, pp: 1699-1710.
  34. Ujvari, B. and Belov, K., 2011. Major histocompatibility complex (MHC) markers in conservation biology. Int J Mol Sci. Vol. 12, No. 8, pp: 5168-5186.
  35. Vera, M.; Sourinejad, I.; Bouza, C.; Vilas, R.; Pino-Querido, A.; Kalbassi, M.R. and Martínez, P., 2011. Phylogeography, genetic structure, and conservation of the endangered Caspian brown trout, Salmo trutta caspius (Kessler, 1877), from Iran. Hydrobiologia. Vol. 664, No. 1, pp: 51-67.