Utility of partial 26S rDNA sequences in DNA-based identification of endemic plants

Öz

Endemic and rare plant taxa are critical components of biodiversity, playing key roles in ecosystem stability and resilience. However, these species are increasingly threatened by habitat loss, climate change, and anthropogenic pressures. Molecular approaches, particularly DNA barcoding, have become essential for accurate species identification and the assessment of genetic diversity. In this study, we evaluated the effectiveness of the partial 26S rDNA region as a DNA barcode marker for the molecular identification of 30 endemic and rare plant species from Kars Province, Türkiye. To our knowledge, this is the first application of the 26S rDNA region in these taxa. Sequence analyses revealed no exact matches in the GenBank database, indicating potential novelty and underscoring the scarcity of reference data. A total of 42 variable sites were identified across the sequences, and phylogenetic analyses largely clustered the species in accordance with their taxonomic families. Importantly, 30 novel barcode sequences were generated and submitted to public databases, offering valuable resources for future taxonomic, phylogenetic, and conservation-oriented studies. This work demonstrates the utility of partial 26S rDNA sequences for the molecular characterization of understudied endemic plants and provides a foundational step toward enhancing biodiversity documentation and conservation efforts in Türkiye.

Anahtar Kelimeler

• Biodiversity
• endemic species
• Kars province
• 26S rDNA
• molecular identification
• phylogenetics

Destekleyen Kurum

KAFKAS UNVERSITY

Proje Numarası

2023-FM-35

Etik Beyan

We have no conflicts of interest to disclose. The study was conducted in accordance with ethical values.

Teşekkür

We would like to thank Prof. Dr. Zeki Kaya for allowing us to use the plant genetics laboratory at Middle East Technical University, Ankara, for some of our experiments. We thank to Asst. Prof. Dr. Muhammet Karadağ for his help in the field work.

Endemik bitkilerin filogenetik tanımlaması için kısmi 26S rDNA dizilerinin kullanımının değerlendirilmesi

Öz

Endemik bitki türleri, biyolojik çeşitliliğin hayati bileşenleridir ve ekosistem sürekliliğine ve direncine katkıda bulunurlar. Ancak bu türlerin birçoğu habitat tahribatı, iklim değişikliği ve insan faaliyetleri nedeniyle artan tehditlerle karşı karşıyadır. Moleküler yaklaşımlar, özellikle DNA barkodlama, endemik bitkilerin genetik çeşitliliğini tanımlamak ve anlamak için gerekli hale gelmiştir. Bu çalışmada, Kars ilinden 30 endemik bitki türünün filogenetik ilişkileri 26S rDNA gen bölgesi kullanılarak araştırılmıştır. Genomik DNA, modifiye CTAB yöntemi kullanılarak izole edilmiş ve 26S rDNA bölgesi bu türler için ilk kez başarılı bir şekilde çoğaltılmış ve dizilenmiştir. Dizi karşılaştırmaları, GenBank veri tabanında tam eşleşme göstermemiştir ve yakın akraba taksonlarla hizalama göstermiştir. Allium czelghauricum ve Fritillaria michailovskyi'nin kayda değer genetik farklılaşma sergilediği ve farklı evrimsel geçmişlere işaret eden toplam 42 değişken bölge tespit edilmiştir. Filogenetik analiz çoğu türü taksonomik ailelerine göre gruplandırmış, ancak muhtemelen taksonomik tutarsızlıklar veya yakınsak evrim nedeniyle bazı beklenmedik gruplanmalar gözlenmiştir. Bu çalışmanın sonuçları, Türkiye'nin endemik florasını anlamak için değerli genetik veriler sağlamakta ve biyoçeşitliliğin korunması için bir temel sunmaktadır.

Anahtar Kelimeler

• Biyoçeşitlilik
• endemik türler
• Kars ili
• 26S rDNA
• moleküler tanımlama
• filogenetik

Proje Numarası

2023-FM-35

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