بررسی بیان ژن گیرندة آندروژن در پاسخ به تغییرات تراکم شکارچی و تراکم نر در ماهی گوپی (Poecilia reticulata)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه شیلات، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران.

2 گروه شیلات، دانشکدة کشاورزی بهارآوران، دانشگاه علمی کاربردی استان قم، قم، ایران.

10.22059/jfisheries.2025.393071.1454

چکیده

ماهی گوپی (Poecilia reticulata) به‌دلیل تنوع رفتاری گسترده در تولیدمثل و در دسترس بودن منابع ژنتیکی و ژنومی، به‌عنوان یک گونة مدل برای مطالعة تکامل رفتارهای تولیدمثلی شناخته می‌شود. آندروژن‌ها به‌عنوان هورمون‌های کلیدی در تنظیم اسپرم‌زایی، از طریق اتصال به گیرندة آندروژن نقش مهمی در کنترل تولیدمثل ایفا می‌کنند. با توجه به اهمیت این مسیر هورمونی، پژوهش حاضر با هدف بررسی تأثیر تراکم‌های مختلف شکارچی و نرهای گوپی بر بیان ژن گیرندة آندروژن انجام شد. در این مطالعه، نمونه‌برداری از ماهیان نر و ماده در چهار بازة زمانی شامل ۵ دقیقه، ۵ ساعت، ۵ روز و ۱۵ روز پس از مواجهه با شکارچی انجام گرفت. نمونه‌ها بلافاصله در نیتروژن مایع فریز شده و تا زمان استخراج RNA در دمای ۸۰- درجة سانتی‌گراد نگهداری شدند. بیان ژن گیرندة آندروژن با استفاده از ژن رفرنس  s18 و روش محاسباتی (-∆∆Ct) 2 تحلیل شد. داده‌ها از نظر نرمال بودن بررسی و برای تحلیل معنی‌داری اثر تیمارها از تجزیه واریانس دوطرفه استفاده شد. نتایج نشان داد تراکم‌های مختلف شکارچی در زمان‌های متفاوت مواجهه، اثر معنی‌داری بر سطح بیان ژن گیرندة آندروژن داشتند (0/05>P)، به‌طوری که در حضور شکارچی، بیان این ژن کاهش یافت. این کاهش بیان ژن به‌طور بالقوه منجر به افت در رفتارهای تولیدمثلی نرهای گوپی شد. این یافته‌ها به درک بهتر از تعامل بین فشارهای زیستی محیطی و تنظیم هورمونی تولیدمثل در گونه‌های مدل کمک می‌کند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of androgen receptor gene expression in response to predator and male densities in Guppy fish (Poecilia reticulata)

نویسندگان [English]

  • Mahdi Katebi 1
  • Amir Reza Abed-Elmdoust 1
  • Hamid Farahmand 1
  • Ali Momeninejad 2
1 Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran.
2 Department of Fisheries, Baharavaran Faculty of Agricultural, University of Applied Science, Qom, Iran.
چکیده [English]

The guppy fish (Poecilia reticulata) is widely recognized as a model species for studying the evolution of reproductive behavior due to its broad range of mating strategies and the availability of genomic and genetic resources. Androgens, as key regulators of spermatogenesis, exert their effects by binding to the Androgen receptor (AR), which plays a critical role in the regulation of reproductive function. Given the importance of this hormonal pathway, the present study aimed to investigate the expression of the androgen receptor gene in response to varying densities of predators and male guppies. Male and female guppies were sampled at four time points: 5 minutes, 5 hours, 5 days, and 15 days after exposure to a predator. Samples were immediately frozen in liquid nitrogen and stored at –80°C until RNA extraction. AR gene expression was analyzed using the reference gene S18 and quantified by the 2^(-∆∆Ct) method. Data normality was assessed, and a two-way ANOVA was performed to determine the statistical significance of treatment effects. Results indicated that predator density had a significant effect on AR gene expression across different time points (P<0.05). Specifically, the presence of predators led to a downregulation of AR gene expression, which is likely associated with reduced reproductive behavior in male guppies. These findings provide valuable insights into how environmental pressures, such as predator and conspecific density, can influence hormonal regulation of reproduction in this model species.

کلیدواژه‌ها [English]

  • Androgen receptor
  • Gene expression
  • Guppy fish
  • Predator
  • Reproduction
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