Spatial analysis of biomineralization associated gene expression from the mantle organ of the pearl oyster Pinctada maxima

Abstract

BackgroundBiomineralization is a process encompassing all mineral containing tissues produced within an organism. One of the most dynamic examples of this process is the formation of the mollusk shell, comprising a variety of crystal phases and microstructures. The organic component incorporated within the shell is said to dictate this architecture. However general understanding of how this process is achieved remains ambiguous. The mantle is a conserved organ involved in shell formation throughout molluscs. Specifically the mantle is thought to be responsible for secreting the protein component of the shell. This study employs molecular approaches to determine the spatial expression of genes within the mantle tissue to further the elucidation of the shell biomineralization.ResultsA microarray platform was custom generated (PmaxArray 1.0) from the pearl oyster Pinctada maxima. PmaxArray 1.0 consists of 4992 expressed sequence tags (ESTs) originating from mantle tissue. This microarray was used to analyze the spatial expression of ESTs throughout the mantle organ. The mantle was dissected into five discrete regions and analyzed for differential gene expression with PmaxArray 1.0. Over 2000 ESTs were determined to be differentially expressed among the tissue sections, identifying five major expression regions. In situ hybridization validated and further localized the expression for a subset of these ESTs. Comparative sequence similarity analysis of these ESTs revealed a number of the transcripts were novel while others showed significant sequence similarities to previously characterized shell related genes.ConclusionsThis investigation has mapped the spatial distribution for over 2000 ESTs present on PmaxArray 1.0 with reference to specific locations of the mantle. Expression profile clusters have indicated at least five unique functioning zones in the mantle. Three of these zones are likely involved in shell related activities including formation of nacre, periostracum and calcitic prismatic microstructure. A number of novel and known transcripts have been identified from these clusters. The development of PmaxArray 1.0, and the spatial map of its ESTs expression in the mantle has begun characterizing the molecular mechanisms linking the organics and inorganics of the molluscan shell.

Cloning and expression analysis of the 37-kDa laminin receptor precursor gene from Hyriopsis cumingii

“…Subsequently, expression was recovered to normal levels due to basic completion of the repair of the shell and mantle, with no significant difference between the two groups. Studies have shown that the secretory capacity of the mantle is recovered following injury (Gardner et al, 2011) with development of the epithelial and glandular cells for 15 days post-injury, which was consistent with our results.…”

Different secretory repertoires control the biomineralization processes of prism and nacre deposition of the pearl oyster shell

“…from nacre and prisms (28,29). On the other hand, approaches at the transcript level performed during these past years have shown that some of these shell proteins, together with other secreted or nonsecreted proteins, exhibited a delimited spatial gene expression in the outer mineralizing mantle-epithelial cells of the pearl oyster (30,31) or of the ormer (32).…”

FLUORESCENT LAMP LIGHT INTENSITY ON THE EMBRYOGENESIS DEVELOPMENT AND THE SURVIVAL OF PEARL OYSTER (Pinctada maxima) LARVAE

“…Sebaliknya pada suhu medium rendah (10°C) dapat menghambat aktivitas enzim dalam mencerna protein, sehingga memperlambat periode inkubasi (Batu, 1982). Mantel adalah organ penting yang berfungsi dalam pembentukan cangkang moluska melalui ekspresi komponen protein dari sel (Gardner et al, 2011).…”