Comparative transcriptomic analysis of left-right sensory differences in Haliotis discus hannai

Area of Science:

• Marine Biology
• Developmental Biology
• Genomics

Background:

• Asymmetric development is common in organisms with symmetrical organs.
• The sensory asymmetry in gastropod mollusks like Haliotis discus hannai is not well understood.

Purpose of the Study:

• To investigate potential asymmetries in the sensory structures of Haliotis discus hannai.
• To explore the molecular basis of sensory asymmetry in mollusks.

Main Methods:

• Transcriptome analysis using RNA-sequencing (RNA-seq) on three sensory structures: eyestalks, cephalic tentacles, and epipodial tentacles.
• Comparative analysis of gene expression between left and right sides of these structures.

Main Results:

• Functional differences were observed in sensory ability and sperm-egg recognition between right and left eyestalks.
• Asymmetries in cytoskeletal organization and cell cycle regulation were found in cephalic tentacles.
• Epipodial tentacles exhibited asymmetries, including differences in immune response.
• The cAMP-protein kinase A (PKA)-CREB-binding protein (CBP) signaling pathway showed asymmetric responses, with CBP being more responsive on the right side.

Conclusions:

• This study provides the first evidence of sensory asymmetry in the gastropod Haliotis discus hannai.
• Identified molecular asymmetries offer insights into the functional differentiation of symmetrical sensory organs in mollusks.
• Findings guide future research into the molecular mechanisms driving asymmetry in symmetrical organs.