Zeytinde (Olea europaea L.) LEA Gen Ailesinin Tanımlanması ve Gen Anlatım Düzeylerinin İncelenmesi

Öz

Zeytin ağacı (Olea europaea L.), Akdeniz tarımında hayati öneme sahip bir bitki olup sık sık kuraklık gibi zorlayıcı koşullara maruz kalmaktadır. Kuraklık toleransını sağlayan moleküler mekanizmalar arasında, Late Embryogenesis Abundant (LEA) proteinleri merkezi bir rol oynamaktadır. Bu hidrofobik proteinler, su kaybı sırasında hücresel koruma sağlamakta, proteinlerin bozulmasını engellemekte, zarları stabilize etmekte ve reaktif oksijen türlerini yok etmektedir. Bu çalışmada, zeytinde LEA proteinlerinin kapsamlı bir filogenetik ve gen anlatımı analizini gerçekleştirdik. Farklı dokularda ifade edilen LEA genlerini tanımladık ve bu genlerin kuraklık stresine karşı verdikleri yanıtları değerlendirmek için diferansiyel gen anlatımı analizi yaptık. LEA aile üyelerini sınıflandırmak için bir filogenetik ağaç oluşturuldu ve evrimsel koruma ile fonksiyonel yanıtları ilişkilendirmek amacıyla anlatım verileri bu ağaca entegre edildi. LEA proteinleri, işlevsel çeşitliliklerini vurgulamak için farklı alt gruplara (LEA_1-5, Dehidrin, SMP) ayrıldı. Ayrıca, dokulara özgü gen anlatımını göstermek için bir ısı haritası oluşturuldu. Sonuçlarımız, zeytinde kuraklık toleransına ilişkin moleküler mekanizmalara değerli bilgiler sağlamakta ve zeytin yetiştiriciliğinde dayanıklılığı artırmaya yönelik genetik iyileştirme için potansiyel hedefler sunmaktadır.

Anahtar Kelimeler

• Zeytin
• Late Embryogenesis Abundant Gen Ailesi
• LEA
• Gen Anlatımı

Identification and Expression Profiling of LEA Gene Family in Olive (Olea europaea L.)

Öz

The olive tree (Olea europaea L.) is a vital crop in Mediterranean agriculture, frequently exposed to harsh drought conditions. Among the molecular mechanisms that confer drought tolerance, Late Embryogenesis Abundant (LEA) proteins play a central role. These hydrophilic proteins function in cellular protection during water deficit, preventing protein denaturation, stabilizing membranes, and scavenging reactive oxygen species. In this study, we performed a comprehensive phylogenetic and gene expression analysis of LEA proteins in olive. We identified LEA genes expressed across different tissues and conducted a differential expression analysis to assess their response to drought stress. A phylogenetic tree was constructed to classify LEA family members, and expression data was mapped onto the tree to link evolutionary conservation with functional responses. LEA proteins were classified into distinct subgroups (LEA_1-5, Dehydrin, SMP) to highlight their functional diversity. Additionally, a tissue-specific expression heatmap was generated to illustrate the spatial dynamics of LEA gene activity. Our results provide valuable insights into the molecular mechanisms of drought tolerance in olive and offer potential targets for genetic improvement to enhance resilience in olive cultivation.

Anahtar Kelimeler

• Olive
• Late Embryogenesis Abundant Gene Family
• LEA
• Gene Expression

Kaynakça

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