Pearl Sac Gene Expression Profiles Associated With Pearl Attributes in the Silver-Lip Pearl Oyster, Pinctada maxima

Pearls are highly prized biomineralized gemstones produced by molluscs. The appearance and mineralogy of cultured pearls can vary markedly, greatly affecting their commercial value. To begin to understand the role of pearl sacs—organs that form in host oysters from explanted mantle tissues that surround and synthesize pearls—we undertook transcriptomic analyses to identify genes that are differentially expressed in sacs producing pearls with different surface and structural characteristics. Our results indicate that gene expression profiles correlate with different pearl defects, suggesting that gene regulation in the pearl sac contributes to pearl appearance and quality. For instance, pearl sacs that produced pearls with surface non-lustrous calcification significantly down-regulate genes associated with cilia and microtubule function compared to pearl sacs giving rise to lustrous pearls. These results suggest that gene expression profiling can advance our understanding of processes that control biomineralization, which may be of direct value to the pearl industry, particularly in relation to defects that result in low value pearls.

Greft İmplantasyonunda İnci Kesesi Oluşumunun Dört Midye Türünde (Unionidae) Karşılaştırılması

In this study, the most suitable mantle part and host mussel species for pearl sac formation were determined. A total of 400 mussels, consisting of four different types (Unio terminalis, Potamida littoralis, Leguminaia wheatleyi and Anodonta pseudodopsis) were used. The average dorso-ventral lengths of the mussels were respectively; 7.89±0.25; 7.28±0.38; 10.68±0.27 and 11.14±0.34 cm. Mantle tissue slices in the size of 3×3 mm obtained from the pallial edge of mantle tissue were used as grafts. Two different mantle sections were identified for graft implantation, one being the mantle cavity and the other was incisions on the mantle tissue. At the end of the three-month pearl culture, the mantle cavity section was identified as the best graft implant site. U. terminalis was determined as the most successful species in terms of survival rate and pearl formation. P. littoralis was the second successful species and L. wheatleyi was the lowest among the species. This study is a guide for long-term pearl production on nacre thickness and quality which are considered important in pearl production.

HISTOLOGI JARINGAN MANTEL TIRAM (SAIBO) PADA BEBERAPA JENIS BIVALVIA SEBAGAI ALTERNATIF IMPLANTASI MUTIARA

All types of bivalves have the potential to produce pearls. Pearls can be produced naturally and cultivated. In cultured pearls, pearl sac are obtained from saibo (slices of another bivalve mantle) that which come from pallial zone. This study wants know the structures of tissues saibo of several species of bivalves as an alternative pearls implantation. This study is conducted from January to March 2017. This study used 7 types of bivalves among others; Pinctada margaritifera, Saccostrea cucullata, Asaphis violascens, Polymesoda bengalensis, Pinna muricata, Volachlamys singaporina, and Tridacna crocea. The method used by staining Hematoxylin-Eosin. Thisstudy show results that every saibo has the different characteristic, but has a common characteristic of having outer epithelium mantle, inner epithelium mantle, muscle fibers, connective tissue and longitudinal muscle, so it can be recommended in pearls implantation Keywords : Saibo, Bivalvia, Implantasi Mutiara[H1] [H1]Disusun berdasarkan abjad