Studies On The Relationships Of Phenotypic Traits Between Pearl And Pinctada Fucata Martensii, And Quantitative Expression Of Biomineralization Genes In Pearl Sac And Mantle

The pearl oyster, Pinctada fucata martensii, is the absolute species for free marine pearl produce in China. The free seawater pearl production need small cells prepared by the mantle of the inner edge of donor and receptor for recipient small cells and bead core of the implant, the formation of the pearl in receptor body. Pearl production experiments, in which saibo dornor and acceptor could be traced for every pearl, were carried out to reveal relationship between saibo dornor or acceptor of P. fucata martensii and pearl quality. using quantitative PCR detected expression levelslof5mineralization genes in the mantle Central (MC), pearl sac (PS) and the outer edge of the mantle (ME). And then analyzed the contaction among the expression level of mineralized gene and pearl nacre thickness. The study results are as follows:Research results of the relationship between pearl quality of free marine pearl and acceptor or dornor aalarge showed:1、There were obvious different L*values of pearl nacrine color both between large siz dornor e group and small size group, and between large size group and middle size group of saibo. An obvious difference of b*values was also observed between large size group and small size group of saibo dornor. there were no significant differences between each group of the rest of the L*value, a*value and b*value2、size of the saibo dornor has a significant effect on the pearl color L*value and b*value, particularly the b*value; There was relevance relationship among pearl color and saibo donor individual, the saibo dornor was bigger the golden pearl more likely to production.3、There were obvious positive relevance relationship among pearl diameter, weight and shell height, total weight and shell weight of P. fucata martensii acceptor, with a correlation coefficient of0.22-0.34. Besides, there were also obvious negative relevance relationship among L*value of pearl and shell height, total weight, shell weight of P. fucata martensii dornor, with a correlation coefficient of-0.08--0.10. Moreover, there were also obvious positive relevance relationships among b*value of pearl and shell height, total weight, shell weight of P. fucata martensii saibo dornor, with a correlation coefficient of0.14,0.09and0.13respectively.4、There were highly significant correlation among L*value of pearls color and L*value of dornor oyster shell surface color (r=0.22, p=0.00); There was a significant negative correlation between L*value of pearls color and L*value of acceptor oyster shell surface color (r=-0.09, p=0.00), There were also highly significant correlation among L*value of pearls color and a*value of dornor oyster shell surface color (r=0.10, p=0.00), There was a significant correlation with a*value of acceptor (r=0.06, p=0.04); There was a significant negative correlation between b*value of pearls color and L*value of dornor (r=-0.07, p=0.02), There was a highly significant correlation with b*value of dornor oyster shell surface color (r=0.16, p=0.00).5、 There were positive relevance relationship among pearl weight, size and acceptor of P. fucata martensii。Fluorescence quantitative PCR analysis showed:①In pearl sac (PS) tissues, the value of relative expression level increased from PP to M, and subsequently to T groups in ACCBP, aspein, efcbp, LRMP4, MP10, KRMP, msi60and prismalin-14.②In the same tissue, no gene is uncorrelated with other shell matrix genes. However, the same shell matrix gene expression levels are uncorrelated among the three tissues, except five genes (aspein, LRMP4, MG1, KRMP and prismalin-14) in the MC tissues are correlated with ME tissues.③The expression levels of the fifteen genes in T and M groups had no significant correlation with pearl layer thickness, except msi60in MC tissue, was observed correlated with pearl nacre thickness (P=0.047). nacrein gene is related to both nacreous and prismatic layer formation.All in all, there is no causal relationship between nacre color of pearls produced from Pinctada fucata martensii and acceptor, and may be affected by the cells of P. fucata martensii dornor, Besides, there were obvious relationship among L*value of inner shell nacrine of P. fucata martensii dornor and s nacre color of pearls. The expression levels of the gene msi60has a certain correlation with nacre thickness of pearls, nacrein gene is related to both nacreous and prismatic layer formation. These findings help to eventually reveal the molecular mechanisms of the mineralized nacre mineralization, and can guide the celection of dornor and acceptor for the pearl production.