Plastid Genome Assembly Using Long-read data

Area of Science:

• * Plant genomics and bioinformatics.
• * Molecular evolution and comparative genomics.

Background:

• * Plastid genome (plastome) structure is generally conserved in seed plants but can undergo significant rearrangements.
• * Long repeat sequences in plastomes complicate assembly using short-read sequencing data, leading to inaccuracies.
• * Single-molecule, long-read sequencing offers a solution, but standardized assembly methods are lacking.

Purpose of the Study:

• * To develop and validate a robust pipeline for assembling plant plastomes using long-read sequencing data.
• * To address the challenges of assembling plastomes with complex repeat structures.
• * To provide a reliable tool for plastome genome assembly.

Main Methods:

• * Development of the plastid Genome Assembly Using Long-read data (ptGAUL) pipeline.
• * Application of ptGAUL to 16 published long-read sequencing datasets (Oxford Nanopore Technologies and Pacific Biosciences).
• * Utilization of ptGAUL for de novo assembly of four Juncus species plastomes.

Main Results:

• * The ptGAUL pipeline efficiently produces accurate and unbiased plastome assemblies with approximately 50× coverage.
• * ptGAUL successfully assembled plastomes from diverse datasets, demonstrating its broad applicability.
• * Analysis of Juncus plastomes revealed numerous long repeats and rearrangements compared to related species.

Conclusions:

• * ptGAUL is an effective tool for accurate and rapid plastome assembly from long-read sequencing data.
• * The pipeline facilitates the study of plastome evolution, particularly in taxa with complex genomic structures.
• * The developed pipeline is publicly available, promoting further research in plant genomics.