GENETIC AND MOLECULAR FOUNDATIONS OF SALT TOLERANCE: TRANSCRIPTOMIC, METABOLOMIC, AND GENOME EDITING APPROACHES

Abstract

Salt stress is one of the most critical abiotic factors limiting agricultural productivity worldwide, triggering complex physiological and molecular responses that reduce plant growth, development, and yield. Salt tolerance is a polygenic trait governed by multifaceted processes, including ion homeostasis, osmotic adjustment, antioxidant defense, hormone signaling, and metabolic reprogramming. This review systematically evaluates the genetic and molecular bases of salt tolerance through transcriptomic (Duan et al., 2023a; Liu et al. 2021), metabolomic (Duan et al., 2023b; Zhang, Z., et al., 2023), and genome editing approaches (Zhang, H., et al., 2023; Zhu et al., 2024), offering an integrated perspective on recent advances. Recent progress in CRISPR–Cas systems has enabled precise modification of ion transporters, transcription factors, and stress-responsive regulatory genes, providing significant improvements in plant salt tolerance (Li et al., 2021; Wang et al., 2022a). Additionally, multi-omics integration has facilitated the elucidation of complex regulatory networks activated under salt stress, yielding comprehensive insights into the molecular determinants of tolerance (Wang et al., 2022b; Yu et al., 2025). Overall, this work presents a holistic analysis of molecular responses to salt stress and provides a robust scientific framework to guide future research and genomic breeding strategies aimed at enhancing salt tolerance in crops.

Keywords

• Salt stress
• Salt tolerance
• Transcriptomics
• Metabolomics
• CRISPR–Cas systems

TUZ TOLERANSININ GENETİK VE MOLEKÜLER TEMELLERİ: TRANSKRİPTOM, METABOLOM VE GEN DÜZENLEME YAKLAŞIMLARI

Abstract

Tuz stresi, dünya genelinde tarımsal üretimi sınırlayan başlıca abiyotik stres faktörlerinden biri olup, bitkilerde büyüme, gelişme ve verim kayıplarına yol açmaktadır. Bu derleme çalışması, tuz stresine karşı bitkilerin geliştirdiği tolerans mekanizmalarını fizyolojik, biyokimyasal ve moleküler düzeylerde bütüncül bir yaklaşımla ele almayı amaçlamaktadır. Çalışmada, ozmotik düzenleme, iyon homeostazı, antioksidan savunma sistemleri ve fotosentetik kapasitenin korunması gibi temel fizyolojik süreçler detaylı biçimde değerlendirilmiştir. Ayrıca, tuz stresine yanıtın moleküler boyutları; hücre içi sinyal iletim mekanizmaları, stresle ilişkili transkripsiyon faktörleri ve epigenetik düzenleyiciler bağlamında incelenmiştir. Transkriptomik ve metabolomik yaklaşımlar aracılığıyla elde edilen bulgular, tuz stresine bağlı gen ekspresyonu ve metabolit profillerindeki dinamik değişimlerin toleransın biyokimyasal temelini oluşturduğunu ortaya koymaktadır. Bununla birlikte, genom düzenleme teknolojilerinin, özellikle hedefe yönelik gen modifikasyonları yoluyla tuz toleransının geliştirilmesinde sunduğu potansiyel vurgulanmıştır. Derleme kapsamında, tuz toleransı araştırmalarının yalnızca tarımsal üretimle sınırlı kalmaması gerektiği; elde edilen moleküler ve fizyolojik bilginin, ürün kalitesi, hasat sonrası değerlendirme ve gıda güvenliği gibi alanlarla da ilişkilendirilmesinin önemi ele alınmıştır. Sonuç olarak bu çalışma, tuz stresine karşı bitkisel toleransın çok katmanlı bir yapı sergilediğini ve bu yapının sistem biyolojisi temelli, disiplinler arası yaklaşımlarla değerlendirilmesinin, sürdürülebilir tarımsal üretim ve güvenli gıda sistemlerinin geliştirilmesi açısından kritik bir rol oynadığını ortaya koymaktadır.

Keywords

• Tuz stresi
• Tuz toleransı
• Transcriptomics
• Metabolomics
• CRISPR–Cas sistemleri

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