Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1

Kurtuluş Özgişi

Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1

Abstract

The utility of internal transcribed spacers (ITSs) in ribosomal RNA sequences for inferring phylogenetic relationships among organisms has been widely established. Although ITS1 sequences exhibit high variability, they possess conserved secondary structures crucial for rRNA gene transcript processing. However, because ITS2 displays a more conserved secondary structure, the structural properties of ITS1 are frequently neglected in systematic studies. In this study, the ITS1 secondary structures of eight Asyneuma taxa endemic to Türkiye were predicted and structurally characterized to evaluate their taxonomical utility. Our findings revealed three distinct structural topologies among the investigated taxa, featuring 4-, 5-, and 6-hairpin models. Detailed structural comparisons among taxa sharing the same hairpin count highlighted distinct sub-branching pattern variations within individual helices. Specifically, among the 4-hairpin taxa, A. davisianum exhibited no branching, whereas A. eximium showed two sub-branches (3a and 3b) on Helix 3, and A. limonifolium subsp. pestalozzae displayed three distinct sub-branches on Helix 3. Furthermore, within the 6-hairpin models, A. linifolium subsp. linifolium possessed two sub-branches on Helix 1, while no secondary branching was observed in A. ilgazense. These specific structural nuances demonstrate that ITS1 secondary structure modeling provides fine-scale morpho-molecular characters for differentiating closely related endemic Asyneuma taxa and offers complementary insights into Campanulaceae taxonomy.

Keywords

Supporting Institution

Scientific and Technological Research Council of Türkiye (TÜBİTAK)

Project Number

121Z359

Ethical Statement

I testify on behalf of all co-authors that our article submitted followed ethical principles in publishing.

Thanks

This study was supported by the Scientific and Technological Research Council of Türkiye (TÜBİTAK) under grant number 121Z359.

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Details

Primary Language

English

Subjects

Botany (Other)

Journal Section

Research Article

Authors

Kurtuluş Özgişi ^*
0000-0002-7344-6666
Türkiye

Early Pub Date

September 14, 2026

Publication Date

-

Submission Date

September 1, 2026

Acceptance Date

September 14, 2026

Published in Issue

Year 2026 Number: Advanced Online Publication

IZ

https://izlik.org/JA97YU88SZ

Cite

RIS / Bibtex

APA

Özgişi, K. (2026). Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1. International Journal of Nature and Life Sciences, Advanced Online Publication, 119-127. https://izlik.org/JA97YU88SZ

AMA

1.Özgişi K. Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1. Int J Nature Life Sci. 2026;(Advanced Online Publication):119-127. https://izlik.org/JA97YU88SZ

Chicago

Özgişi, Kurtuluş. 2026. “Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1”. International Journal of Nature and Life Sciences, no. Advanced Online Publication: 119-27. https://izlik.org/JA97YU88SZ.

EndNote

Özgişi K (September 1, 2026) Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1. International Journal of Nature and Life Sciences Advanced Online Publication 119–127.

IEEE

[1]K. Özgişi, “Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1”, Int J Nature Life Sci, no. Advanced Online Publication, pp. 119–127, Sept. 2026, [Online]. Available: https://izlik.org/JA97YU88SZ

ISNAD

Özgişi, Kurtuluş. “Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1”. International Journal of Nature and Life Sciences. Advanced Online Publication (September 1, 2026): 119-127. https://izlik.org/JA97YU88SZ.

JAMA

1.Özgişi K. Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1. Int J Nature Life Sci. 2026;:119–127.

MLA

Özgişi, Kurtuluş. “Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1”. International Journal of Nature and Life Sciences, no. Advanced Online Publication, Sept. 2026, pp. 119-27, https://izlik.org/JA97YU88SZ.

Vancouver

1.Kurtuluş Özgişi. Secondary Structure and Sequence Divergence in Endemic Asyneuma Taxa (Campanulaceae): Implications for Systematics ITS1. Int J Nature Life Sci [Internet]. 2026 Sep. 1;(Advanced Online Publication):119-27. Available from: https://izlik.org/JA97YU88SZ