A diecast mineralization process forms the tough mantis shrimp dactyl club

Abstract

Biomineralization, the process by which mineralized tissues grow and harden via biogenic mineral deposition, is a relatively lengthy process in many mineral-producing organisms, resulting in challenges to study the growth and biomineralization of complex hard mineralized tissues. Arthropods are ideal model organisms to study biomineralization because they regularly molt their exoskeletons and grow new ones in a relatively fast timescale, providing opportunities to track mineralization of entire tissues. Here, we monitored the biomineralization of the mantis shrimp dactyl club—a model bioapatite-based mineralized structure with exceptional mechanical properties—immediately after ecdysis until the formation of the fully functional club and unveil an unusual development mechanism. A flexible membrane initially folded within the club cavity expands to form the new club’s envelope. Mineralization proceeds inwards by mineral deposition from this membrane, which contains proteins regulating mineralization. Building a transcriptome of the club tissue and probing it with proteomic data, we identified and sequenced Club Mineralization Protein 1 (CMP-1), an abundant mildly phosphorylated protein from the flexible membrane suggested to be involved in calcium phosphate mineralization of the club, as indicated by in vitro studies using recombinant CMP-1. This work provides a comprehensive picture of the development of a complex hard tissue, from the secretion of its organic macromolecular template to the formation of the fully functional club.

Bioinspired functionally graded composite assembled using cellulose nanocrystals and genetically engineered proteins with controlled biomineralization

“…We also observed this trend while investigating apatite mineralization in native dactyl clubs, in particular nding that CMP-1 can mediate nucleation and growth of apatite crystals on the surface of the chiral nematic chitin 3D framework. 14 CMP-1 undergoes LLPS induced by Ca 2+ ions and we suggested that this preassembly could be a key intermediate step in the biofabrication of the club by increasing the local concentration of Ca 2+ ions in order to accelerate the biomineralization process. 14 To this end, we explored whether MP1, (Figure 2d) could induce biomimetic apatite mineralization on the surface of the helicoidally-organized RP4/CNC 3D framework and emulate the highly mineralized external impact region of the dactyl club.…”

“…14 CMP-1 undergoes LLPS induced by Ca 2+ ions and we suggested that this preassembly could be a key intermediate step in the biofabrication of the club by increasing the local concentration of Ca 2+ ions in order to accelerate the biomineralization process. 14 To this end, we explored whether MP1, (Figure 2d) could induce biomimetic apatite mineralization on the surface of the helicoidally-organized RP4/CNC 3D framework and emulate the highly mineralized external impact region of the dactyl club. We incubated MP1 for 24 days with modified simulated body fluid (SBF) (pH ~7.4) 34 and probed apatite biomineralization using polarized light microscopy (PLM) (Figure 4a).…”

“…[24][25][26][27] Key advantages of concentrated coacervates include increased intermolecular interactions, low viscosity and interfacial tension, all of which greatly facilitate wetting and in ltration through the CNC network to result in strong binding to the reinforcing phase and, in turn, to high adhesive properties that could not be achieved in the absence of coacervation (Figure 2h). [20][21][22][23] Furthermore, we have recently found that CMP-1 in the club of the peacock mantis shrimp has a 3-block primary structure (Figure 2d) 14 that may result in all three of the characteristics required to act as a matrix of a tough biocomposite. First, it has a conserved mid-block carbohydrate-binding module that is likely used as an anchor to chitin brils in the club.…”

“…Finally, MP1, the mineralizing protein, was designed to mimic the highly mineralized hard exterior impact region of the club. It is a modi ed version of RP4 whereby the C-terminus CBM was replaced with the Asp-rich cluster residues 131-293 from CMP-1 14 (called eCMP1 Asp ), and all the poly-Lys stretches of eBGWSilEl (+) 4 were mutated to glutamic acid (Glu).…”

Investigation of microstructure and dissimilar materials connection patterns of mantis shrimp saddle

“…The typical helicoidal structure was used in new material design widely (Dimas, Bratzel, Eylon, & Buehler, 2013; Haug, Haug, Maas, Kutschera, & Waloszek, 2010; Holmes & Riddick, 2014; Wegst, Bai, Saiz, Tomsia, & Ritchie, 2015). Compared with the smasher, the spearer also owned the layered helicoidal structure with highly mineralized impact region (Aminia et al, 2019). Moreover, the unique striated region composed of mineralized fibers facilitated redeployment of a raptorial feeding appendage of spearer (Grunenfelder et al, 2018).…”