مکانیسم‌های افزایش تولید پروتئین‌های نوترکیب در کلروپلاست گیاهان

نوع مقاله: علمی - پژوهشی

نویسندگان

1 دانشیار گروه اصلاح نباتات و بیوتکنولوژی کشاورزی، دانشکده کشاورزی، دانشگاه تربیت مدرس، تهران

2 دانشجوی دکتری بیوتکنولوژی کشاورزی، دانشکده کشاورزی، دانشگاه فردوسی مشهد، مشهد

3 دانشجویان دکتری اصلاح نباتات، دانشکده کشاورزی، دانشگاه تربیت مدرس، تهران

4 دانشجوی دکتری نانوبیوتکنولوژی، دانشکده علوم زیستی، دانشگاه تربیت مدرس، تهران

چکیده

چکیده
    تولید پروتئین‌های ارزشمند داروئی و مهم کاربردی در حجم انبوه و ارزان از طریق گیاهان، زراعت مولکولی نام دارد. زراعت مولکولی و تولید پروتئین‌های نوترکیب در گیاهان تراریخت کلروپلاستی در ایران با موفقیت‌های ارزشمندی همراه بوده است که تولید پروتئین‌های داروئی انسولین، اینترفرون گاما، فعال کننده‌ی پلاسمینوژن بافتی و ... نمونه‌هایی از این موفقیت‌ها می‌باشند. به‌دلیل نیاز روز افزون به پروتئین‌های نوترکیب، انتخاب یک سیستم بیانی مناسب برای تولید آن‌ها حائز اهمیت است. مهندسی ژنوم کلروپلاست به دلیل داشتن مزایای بسیار، یکی از روش‌های مناسب برای تولید پروتئین‌های نوترکیب می‌باشد. به منظور دستیابی به سطوح بالای پروتئین‌های نوترکیب در اندامک کلروپلاست بایستی با توجه به سیستم رونویسی، ترجمه و تغییرات پس از ترجمه در این اندامک به نحوی کارآمد از پتانسیل‌های بیانی آن بهره گرفت. از جمله راه‌کارهای افزایش میزان پروتئین خارجی در کلروپلاست می‌توان به درج ژن در محل مناسب در ژنوم کلروپلاست، استفاده از راه‌انداز قوی، استفاده از توالی‌های تنظیمی مناسب در انتهای ׳5 و ׳3 ژن‌های ورودی، بهینه‌‌سازی کدونی و استفاده از عوامل افزایش‌دهنده پایداری پروتئین نظیر چاپرون‌ها و پروتئین‌های فیوژن اشاره کرد. بر اساس یافته‎های اخیر در زمینه تولید پروتئین‌های نوترکیب و زراعت مولکولی، در این مقاله تلاش گردیده تا ضمن معرفی مختصر کلروپلاست و ژنوم آن، مکانیسم‌های افزایش میزان پروتئین‌های نوترکیب در گیاهان تراریخت کلروپلاستی مورد بحث و بررسی قرار گیرد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Mechanisms to Increase the Production of Recombinant Proteins in Plant Chloroplasts

نویسندگان [English]

  • Mokhtar Jalali Javaran 1
  • Mozhgan Soleimanizadeh 2
  • Babak Latif 3
  • Shahla Razmi 3
  • Melina Yarbakht 4
1 Associate Professor, Department of Plant Breeding, Faculty of Agriculture, Tarbiat Modares University, Tehran
2 Ph.D. Student of Biotechnology, Department of Biotechnology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad
3 Ph.D. Student of Plant Breeding, Department of Plant Breeding, Faculty of Agriculture, Tarbiat Modares University, Tehran
4 Ph.D. Student of Nano-Biotechnology, Department of Nano-Biotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran
چکیده [English]

Abstract
Molecular farming is the use of plants to produce valuable pharmaceutical proteins in the bulky and cost-effective manner. Molecular farming and the production of recombinant proteins (such as insulin, interferon-gamma, tissue plasminogen activator, etc.) in transplastomic plants, has achieved a great success in Iran. Due to the growing demand for recombinant proteins, the selection of a proper expression system is very important. Chloroplast genome engineering, for its many advantages, is one of the suitable methods for the production of recombinant proteins. To achieve high levels of recombinant proteins in chloroplasts, plastid’s specific transcription, translation and post-translational modifications should be considered. Some of the strategies used for increasing of foreign proteins in chloroplast can be mentioned: gene insertion in the suitable site in chloroplast genome, use of strong promoters, appropriate regulatory sequences in the 5' and 3' UTRs, codon optimization, and utilization of factors enhancing protein stability such as chaperons and fusion proteins. In this article, besides a brief description about chloroplast and its genome, methods for enhancing recombinant protein production in transplastomic plants were discussed.
 

کلیدواژه‌ها [English]

  • Protein stability
  • Molecular farming
  • Enhancement of recombinant protein production
  • Chloroplast genome engineering
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