In this study,we investigated the impact of water temperature on pearl formation and the molecular mechanisms underlying this biomineralization process in the mussel Hyriopsis cumingii.In the laboratory experiment,rec...In this study,we investigated the impact of water temperature on pearl formation and the molecular mechanisms underlying this biomineralization process in the mussel Hyriopsis cumingii.In the laboratory experiment,recipient mussels received saibo grafts from donor mussels and then were cultivated at five temperatures(16,20,24,28,and 32◦C)for 1 month.We found that speed of pearl formation varied with water temperature:there was no visible pearl granules at 16 and 20◦C,tawny pearl granules were collected at 24◦C and lustrous pearl granules were collected at 28 and 32◦C.The expressions of several nacreous layer matrix protein genes(hic22,hic24,HcTyr Hc-upsalin and Hcperlucin)at 28◦C and 32◦C were peaked on day 28,and the expressions of other nacreous layer matrix protein genes(hic52 and hic74)on day 28 were significant higher than day 14.In the natural environment,pearl deposition rate also increased as water temperature rose,and the optimum range for pearl growth in H.cumingii was between 28.3 and 30.3◦C.Expression of the prismatic layer-related matrix protein genes hic31 and both prismatic and nacreous layer-related matrix protein gene silkmapin was significantly high in winter,and expressions of the nacreous layer-related matrix protein genes(hic24,hic74,HcTyr,Hc-upsalin and Hcperlucin)were always higher during higher temperature seasons compared with winter.These results indicate that high water temperature can speed up pearl formation and further regulate matrix protein secretion to accelerate pearl nacre deposition.展开更多
Organic matrix proteins play an important role in the biomineralization of mollusc shells.We have identified and characterized a novel matrix protein,namely hic74,isolated from the mantle of the freshwater mussel Hyri...Organic matrix proteins play an important role in the biomineralization of mollusc shells.We have identified and characterized a novel matrix protein,namely hic74,isolated from the mantle of the freshwater mussel Hyriopsis cumingii.The hic74 gene encodes a 850 amino acid protein that is rich in alanine(ala,30.8%),glycine(gly,25.8%)and serine(ser,10.6%),with ala mainly existing in poly-ala forms within the ala/gly-rich regions.Quantitative PCR expression analysis demonstrated that hic74 was specifically amplified from the mantle and in situ hybridization showed a strong signal in the epithelial cells in the pallial region of the mantle.Lower levels of expression were detected during the early stages of pearl sac formation but increased and remained constant during nacreous layer formation suggesting that hic74 might be involved in this process.展开更多
Heat shock protein 90(HSP90)represents a suite of highly conserved and multi-functional molecular chaperone proteins that play an important role in cellular stress responses.In order to better understand the expressio...Heat shock protein 90(HSP90)represents a suite of highly conserved and multi-functional molecular chaperone proteins that play an important role in cellular stress responses.In order to better understand the expression of HSP90 in mollusks,a full-length complementary DNA(cDNA)of HSP90(HcHSP90)was identified in Hyriopsis cumingii.HcHSP90 cDNA was 2659 bp in length,consisting of 30 and 50-untranslated regions and an open reading frame of 2187 bp,that encoded a 728 amino acid protein.Homology analyses showed that the HcHSP90 protein was highly conserved and had 5 well-conserved family signatures of HSP90 proteins.HcHSP90 mRNA expressed in various tissues of H.cumingii.The expression level of HcHSP90 was the highest in the digestive gland.In all tissues,with the exception of the digestive gland where it was down-regulated,HcHSP90 mRNA expression was significantly induced by temperature treatments(0,5,25,and 35℃)relative to the control(15℃).Exposure of H.cumingii to different concentrations of cadmium(50,100,and 200 mg/L),up-regulated HcHSP90 mRNA in the haemolymph and gill but without an obvious dose-dependent response.When H.cumingii were infected with Aeromonas hydrophila,HcHSP90 mRNA expression in the haemolymph was up-regulated and peaked 36 h post-infection,while in the gills it was significantly up-regulated 3 h post-infection in the gills,then remained constant until returning to pre-challenge expression levels at 36 h post-infection.The results show that HcHSP90 expression can be significantly regulated by changes in temperature,cadmium exposure and bacterial infection.We deduced that HSP90 may play an important role in helping H.cumingii to cope with environmental stress.展开更多
UroporphyrinogenⅢsynthetase(UROS)is an important enzyme involved in the structural formation of porphyrin,which is responsible for color intensity.A UROS homolog was isolated and characterized from the pearl mussel,H...UroporphyrinogenⅢsynthetase(UROS)is an important enzyme involved in the structural formation of porphyrin,which is responsible for color intensity.A UROS homolog was isolated and characterized from the pearl mussel,Hyriopsis cumingii(HcUros).The HcUros cDNA was 858 bp in length with an open reading frame that encoded a 285 amino acid protein,which contained a conserved HemD domain.HcUros exhibited widespread tissue distribution,displaying particular enrichment in the mantle and haemolymph of purple mussels,compared to white mussels.In situ hybridization of HcUros in mantle tissue demonstrated that it was specifically expressed in the dorsal epithelial cells of the mantle pallia.Additionally,HcUros expression was upregulated following implantation of the pearl sac to produce pearls.The data suggest that HcUros contributes to shell pigmentation,and nacre formation and coloring in H.cumingii.展开更多
Shell biomineralization is a process in which inorganic minerals assemble under accuracy control of macromolecule,mainly the matrix proteins.A shell-notching assay was used in Hyriopsis cumingii and CaCO3 deposition d...Shell biomineralization is a process in which inorganic minerals assemble under accuracy control of macromolecule,mainly the matrix proteins.A shell-notching assay was used in Hyriopsis cumingii and CaCO3 deposition during shell regeneration and the expression pattern of five shell matrix protein encoding genes,HcTyp-1,hic31,hic52,silkmapin and Hcperlucin were analyzed.Macro-and microscopic observation revealed that shell regeneration can be broadly separated into three stages.(1)The formative period of the periostracum(from 0th day to 6thday),the pellicle formed and covered the gap creating a sealed space for mineralized layer origin.(2)The period of prismatic layer mineralization(from 14 to 21 days),the periostracum continued to grow,and aragonite seeds originated from the organic membrane accumulated and grew laterally to cover the whole periostracum.(3)The growth period of the nacreous layer(from 29 to 39 days),the initial nacreous layer formed,and regular aragonite crystals deposited,nucleated and eventually grew to form a distinctive brick wall structure.Furthermore,the periodic high-expression of five shell matrix protein genes during periostracum formation and prismatic or nacreous layer mineralization suggested they had a dominant role in the programmed reparative process.These observations contribute to understanding the molecular mechanism of shell formation.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(32072975)the Modern Agro-industry Technology Research System(CARS-49)the Project of Shanghai Engineering and Technology Center for Promoting Ability(16DZ2281200).
文摘In this study,we investigated the impact of water temperature on pearl formation and the molecular mechanisms underlying this biomineralization process in the mussel Hyriopsis cumingii.In the laboratory experiment,recipient mussels received saibo grafts from donor mussels and then were cultivated at five temperatures(16,20,24,28,and 32◦C)for 1 month.We found that speed of pearl formation varied with water temperature:there was no visible pearl granules at 16 and 20◦C,tawny pearl granules were collected at 24◦C and lustrous pearl granules were collected at 28 and 32◦C.The expressions of several nacreous layer matrix protein genes(hic22,hic24,HcTyr Hc-upsalin and Hcperlucin)at 28◦C and 32◦C were peaked on day 28,and the expressions of other nacreous layer matrix protein genes(hic52 and hic74)on day 28 were significant higher than day 14.In the natural environment,pearl deposition rate also increased as water temperature rose,and the optimum range for pearl growth in H.cumingii was between 28.3 and 30.3◦C.Expression of the prismatic layer-related matrix protein genes hic31 and both prismatic and nacreous layer-related matrix protein gene silkmapin was significantly high in winter,and expressions of the nacreous layer-related matrix protein genes(hic24,hic74,HcTyr,Hc-upsalin and Hcperlucin)were always higher during higher temperature seasons compared with winter.These results indicate that high water temperature can speed up pearl formation and further regulate matrix protein secretion to accelerate pearl nacre deposition.
基金This work was supported by the National Science and Technology Support Program(2012BAD26B04)the National Natural Science Foundation of China(31272657)Shanghai Collaborative Innovation Center for Aquatic Animal Genetics and Breeding(ZF1206).
文摘Organic matrix proteins play an important role in the biomineralization of mollusc shells.We have identified and characterized a novel matrix protein,namely hic74,isolated from the mantle of the freshwater mussel Hyriopsis cumingii.The hic74 gene encodes a 850 amino acid protein that is rich in alanine(ala,30.8%),glycine(gly,25.8%)and serine(ser,10.6%),with ala mainly existing in poly-ala forms within the ala/gly-rich regions.Quantitative PCR expression analysis demonstrated that hic74 was specifically amplified from the mantle and in situ hybridization showed a strong signal in the epithelial cells in the pallial region of the mantle.Lower levels of expression were detected during the early stages of pearl sac formation but increased and remained constant during nacreous layer formation suggesting that hic74 might be involved in this process.
基金This study was supported by the National Natural Science Foundation of China(31101939)the Key Fundamental Research Project of Shanghai Municipal Science and Technology Committee(10JC1406300)the Innovation Program of Shanghai Municipal Education Commission(13ZZ128).
文摘Heat shock protein 90(HSP90)represents a suite of highly conserved and multi-functional molecular chaperone proteins that play an important role in cellular stress responses.In order to better understand the expression of HSP90 in mollusks,a full-length complementary DNA(cDNA)of HSP90(HcHSP90)was identified in Hyriopsis cumingii.HcHSP90 cDNA was 2659 bp in length,consisting of 30 and 50-untranslated regions and an open reading frame of 2187 bp,that encoded a 728 amino acid protein.Homology analyses showed that the HcHSP90 protein was highly conserved and had 5 well-conserved family signatures of HSP90 proteins.HcHSP90 mRNA expressed in various tissues of H.cumingii.The expression level of HcHSP90 was the highest in the digestive gland.In all tissues,with the exception of the digestive gland where it was down-regulated,HcHSP90 mRNA expression was significantly induced by temperature treatments(0,5,25,and 35℃)relative to the control(15℃).Exposure of H.cumingii to different concentrations of cadmium(50,100,and 200 mg/L),up-regulated HcHSP90 mRNA in the haemolymph and gill but without an obvious dose-dependent response.When H.cumingii were infected with Aeromonas hydrophila,HcHSP90 mRNA expression in the haemolymph was up-regulated and peaked 36 h post-infection,while in the gills it was significantly up-regulated 3 h post-infection in the gills,then remained constant until returning to pre-challenge expression levels at 36 h post-infection.The results show that HcHSP90 expression can be significantly regulated by changes in temperature,cadmium exposure and bacterial infection.We deduced that HSP90 may play an important role in helping H.cumingii to cope with environmental stress.
基金the National Key R&D Program of China(2018YFD0901406)the National Natural Science Foundation of China(31872565)sponsored by the Program of the Shanghai Academic Research Leader(19XD1421500).
文摘UroporphyrinogenⅢsynthetase(UROS)is an important enzyme involved in the structural formation of porphyrin,which is responsible for color intensity.A UROS homolog was isolated and characterized from the pearl mussel,Hyriopsis cumingii(HcUros).The HcUros cDNA was 858 bp in length with an open reading frame that encoded a 285 amino acid protein,which contained a conserved HemD domain.HcUros exhibited widespread tissue distribution,displaying particular enrichment in the mantle and haemolymph of purple mussels,compared to white mussels.In situ hybridization of HcUros in mantle tissue demonstrated that it was specifically expressed in the dorsal epithelial cells of the mantle pallia.Additionally,HcUros expression was upregulated following implantation of the pearl sac to produce pearls.The data suggest that HcUros contributes to shell pigmentation,and nacre formation and coloring in H.cumingii.
基金This work was financially supported by Modern Agro-industry Technology Research System(CARS-49)the National Natural Science Foundation of China(31672654)the Project of Shanghai Engineering and Technology Center for Promoting Ability of shanghai(16DZ2281200).
文摘Shell biomineralization is a process in which inorganic minerals assemble under accuracy control of macromolecule,mainly the matrix proteins.A shell-notching assay was used in Hyriopsis cumingii and CaCO3 deposition during shell regeneration and the expression pattern of five shell matrix protein encoding genes,HcTyp-1,hic31,hic52,silkmapin and Hcperlucin were analyzed.Macro-and microscopic observation revealed that shell regeneration can be broadly separated into three stages.(1)The formative period of the periostracum(from 0th day to 6thday),the pellicle formed and covered the gap creating a sealed space for mineralized layer origin.(2)The period of prismatic layer mineralization(from 14 to 21 days),the periostracum continued to grow,and aragonite seeds originated from the organic membrane accumulated and grew laterally to cover the whole periostracum.(3)The growth period of the nacreous layer(from 29 to 39 days),the initial nacreous layer formed,and regular aragonite crystals deposited,nucleated and eventually grew to form a distinctive brick wall structure.Furthermore,the periodic high-expression of five shell matrix protein genes during periostracum formation and prismatic or nacreous layer mineralization suggested they had a dominant role in the programmed reparative process.These observations contribute to understanding the molecular mechanism of shell formation.
