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


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


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.


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
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