Reference assembly and gene expression analysis of Apostichopus japonicus larval development

Area of Science:

• Marine Biology
• Genomics
• Developmental Biology

Background:

• Understanding holothurian development is crucial for aquaculture.
• A comprehensive transcriptome is needed for Apostichopus japonicus.

Purpose of the Study:

• To generate the most complete transcriptome assembly for Apostichopus japonicus.
• To identify differentially expressed transcription factors and genetic variations.
• To explore the genetic basis of planktotrophic development and immune response.

Main Methods:

• RNA sequencing (RNA-seq) of four developmental stages (blastula, gastrula, auricularia, pentactula).
• Assembly of transcriptome data using Illumina sequencing and existing paired-end reads.
• Bioinformatic analysis including differential gene expression, SNP/indel identification, and Gene Ontology (GO) enrichment.

Main Results:

• Achieved the most complete A. japonicus transcriptome assembly to date.
• Identified 174 differentially expressed transcription factors, including stage-specific ones.
• Discovered 1,174,999 single nucleotide polymorphisms (SNPs) and 58,932 indels.
• GO enrichment analysis highlighted terms related to immune response.

Conclusions:

• The study provides a valuable genomic resource for A. japonicus.
• Identified key factors for understanding holothurian planktotrophic development.
• Findings support applications in commercial sea cucumber breeding programs.