Dataset Information

A de novo chromosome-scale assembly of the Lablab purpureus genome.

ABSTRACT:

Introduction

Lablab (Lablab purpureus (L.) Sweet), an underutilized tropical legume crop, plays a crucial role in global food and nutritional security. To enhance our understanding of its genetic makeup towards developing elite cultivars, we sequenced and assembled a draft genome of L. purpureus accession PK2022T020 using a single tube long fragment read (stLFR) technique.

Results and discussion

The preliminary assembly encompassed 367 Mb with a scaffold N50 of 4.3 Mb. To improve the contiguity of our draft genome, we employed a chromatin contact mapping (Hi-C) approach to obtain a pseudochromosome-level assembly containing 366 Mb with an N50 length of 31.1 Mb. A total of 327.4 Mb had successfully been anchored into 11 pseudomolecules, corresponding to the haploid chromosome number in lablab. Our gene prediction recovered 98.4% of the highly conserved orthologs based on the Benchmarking Universal Single-Copy Orthologs (BUSCO) analysis. Comparative analyses utilizing sequence information from single-copy orthologous genes demonstrated that L. purpureus diverged from the last common ancestor of the Phaseolus/Vigna species approximately 27.7 million years ago. A gene family expansion analysis revealed a significant expansion of genes involved in responses to biotic and abiotic stresses. Our high-quality chromosome-scale reference assembly provides an invaluable genomic resource for lablab genetic improvement and future comparative genomics studies among legume species.

SUBMITTER: Pootakham W

PROVIDER: S-EPMC10948561 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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Publications

A <i>de novo</i> chromosome-scale assembly of the <i>Lablab purpureus</i> genome.

Pootakham Wirulda W Somta Prakit P Kongkachana Wasitthee W Naktang Chaiwat C Sonthirod Chutima C U-Thoomporn Sonicha S Yoocha Thippawan T Phadphon Poompat P Tangphatsornruang Sithichoke S

Frontiers in plant science 20240305

<h4>Introduction</h4>Lablab (<i>Lablab purpureus</i> (L.) Sweet), an underutilized tropical legume crop, plays a crucial role in global food and nutritional security. To enhance our understanding of its genetic makeup towards developing elite cultivars, we sequenced and assembled a draft genome of <i>L. purpureus</i> accession PK2022T020 using a single tube long fragment read (stLFR) technique.<h4>Results and discussion</h4>The preliminary assembly encompassed 367 Mb with a scaffold N50 of 4.3 M ...[more]

PMID: 38504891

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