Project description:BackgroundThe polyplacophoran mollusks (chitons) possess serially arranged shell plates. This feature is unique among mollusks and believed to be essential to explore the evolution of mollusks as well as their shells. Previous studies revealed several cell populations in the dorsal epithelium (shell field) of polyplacophoran larvae and their roles in the formation of shell plates. Nevertheless, they provide limited molecular information, and shell field morphogenesis remains largely uninvestigated.ResultsIn the present study, we investigated shell field development in the chiton Acanthochitona rubrolineata based on morphological characteristics and molecular patterns. A total of four types of tissue could be recognized from the shell field of A. rubrolineata. The shell field comprised not only the centrally located, alternatively arranged plate fields and ridges, but also the tissues surrounding them, which were the precursors of the girdle and we termed as the girdle field. The girdle field exhibited a concentric organization composed of two circularly arranged tissues, and spicules were only developed in the outer circle. Dynamic engrailed expression and F-actin (filamentous actin) distributions revealed relatively complicated morphogenesis of the shell field. The repeated units (plate fields and ridges) were gradually established in the shell field, seemingly different from the manners used in the segmentation of Drosophila or vertebrates. The seven repeated ridges also experienced different modes of ontogenesis from each other. In the girdle field, the presumptive spicule-formation cells exhibited different patterns of F-actin aggregations as they differentiate.ConclusionsThese results reveal the details concerning the structure of polyplacophoran shell field as well as its morphogenesis. They would contribute to exploring the mechanisms of polyplacophoran shell development and molluscan shell evolution.

| S-EPMC10080879 | biostudies-literature

Acanthochitona

Project description:Acanthochitona sp. overview

| PRJNA1082861 | ENA

Project description:RNA-seq of Acanthochitona rubrolineata

| PRJNA515172 | ENA

Proteomic analysis of biomineralization proteins in the shell plate and spicule of chiton Acanthochitona rubrolineata

Project description:Chitons are ancient polyplacophora mollusk covered with biominerals that may shed light on the origin and evolution of biomineralization. While the body plan of chitons is strictly conservative since the Cambrian, the conservation degree of biomineralized mechanisms among chitons are unclear. Hence, we extracted the matrix proteins of two biominerals (shell plates and spicules) from Acanthochitona rubrolineata, which is widely distributed in the coastal region of China. Liquid chromatography coupled to tandem mass spectrometry was utilized to obtain their proteome information, and proteomic analysis was performed with the species-specific transcriptome library. By comparing biomineralization proteins of Acanthopleura loochooana from the southeastern coast of China, the von Willebrand factor type A domain, chitin-binding domain, ferritin, and cadherin are found to be shared in both species. This study provides an important reference for understanding the evolutionary conservatism on chiton biomineralization.

2025-03-05 | PXD061516 |

Morus alba Raw protein sequence reads

Project description:Morus alba L. Raw protein sequence reads and sequence

2024-02-08 | PXD049451 |