Identification of Shell Color-Associated Genes Using Mantle Branch-Specific RNA Sequencing of Yellow-Colored Line of Pearl Oyster Pinctada fucata martensii

The yellow-colored line of pearl oyster Pinctada fucata martensii displays a yellow prismatic layer and a white nacreous layer that can be used as an ideal model for research on shell color formation.Micro-Raman spectroscopy and transcriptome analyses were performed to explore the potential molecular mechanism underlying the phenotype differentiation.The micro-Raman spectroscopy results indicate that the prismatic layer exhibits distinct characteristic peaks of carotenoids,while these peaks are not prominent in the nacreous layer.In the transcriptome comparison of the central zone of mantle and mantle edge tissue,which function in nacreous and prismatic layer formation,respectively,935 significantly differentially expressed genes(DEGs)were identified,with 385 genes upregulated and 227 genes downregulated(|log_(2)(Fold change)|>1 and false discovery rate<0.05)in the mantle edge tissue.Among these genes,some were associated with melanoma/melanogenesis,such as tyrosinase,zinc metalloprotease,glutathione S-transferase,and ATP-binding cassette sub-family;some were associated with the carotenoid-related pathway,including scavenger receptors,cytochrome P450 and lipoprotein receptor.Genes associated with porphyrin metabolism,including porphobilinogen deaminase,and copper/zinc superoxide dismutase,and genes associated with shell matrix protein,including amorphous calcium carbonate binding protein,shematrin,PIF,and collagen,also exhibited significantly different expressions.It is speculated that the different colours between prismatic layer and nacreous layer in the yellow-colored line of P.f.martensii might be resulted from melanin,carotenoids and porphyrin metabolism,while genes related to shell structure and biomineralization might also affect coloration.Our results provide new insights to understand the mechanism of shell color formation in mollusca.

Comparison of growth and survival of larvae among different shell color stocks of bay scallop Argopecten irradians irradians(Lamarck 1819)

In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis.

Relationship Between Shell Color and Growth and Survival Traits in the Pacific Oyster Crassostrea gigas

Shell color is regarded as an economic trait in many breeding programs of bivalve mollusks,but the relationship between shell color and production traits remains controversial.In our breeding program of Crassostrea gigas,solid white,black,and orange shell lines were obtained,and second-generation(F2)and testcross families with segregating shell colors were constructed by crossing these three lines.These segregating families provided ideal samples for investigating the relationship between shell color and production traits in C.gigas.The growth and survival of 7-month-old oysters with different shell colors sampled within the same families were compared in seven F2 families and 13 testcrosses.In addition,the growth and survival of oysters from the three shell color lines were compared at 4 and 16 months of age.The growth and survival rates of the orange shell line were significantly lower than those of the white and black shell lines.However,no significant difference in growth between oysters with different shell colors was observed within segregating families,except the testcrosses produced by crossing orange-and white-shelled grandparents,and no significant difference in survival was observed in any family.Overall,no significant correlation was observed between shell color and production traits in C.gigas.These results suggest that shell color cannot be used as a marker to guide the selection of growth and survival traits.Thus shell color and production traits should be selected independently in oyster breeding programs.

De novo transcriptome sequencing reveals candidate genes involved in orange shell coloration of bay scallop Argopecten irradians

Molluscan shell color has received persistent attention for its distinctive diversity and complexity. In the present study, six transcriptome libraries obtained from two developmental stages, pre-pigmentation and post-pigmentation, were used for paired-end sequencing in the bay scallop Argopecten irradians. In total, 289 839 646 paired-end reads were assembled into 70 929 transcripts. Using BLASTX and BLASTN, 30 896 unigenes were successfully annotated against the SWISS-PROT, NR, and KOG database. Gene ontology annotation and Kyoto Encyclopedia of Genes and Genomes classification identified numbers of unigenes involved in biomineralization and pigmentation. Digital gene expression analysis revealed that melanin, trace metal elements and porphyrins are potentially involved in shell coloration of A. irradians.

Characteristics of a Novel Tyrosinase Gene Involved in the Formation of Shell Color in Hard Clam Meretrix meretrix

Hard clam(Meretrix meretrix)has a rich shell color variation among individuals from light yellow to bluish gray,brown red,and black,which may associating with melanin.Tyrosinase(Tyr)is a key rate-limiting enzyme for the biosynthesis of melanin,which affects the dark color of animal skin,hair,fur,scales and feathers.Here,we isolated and characterized the full-length cDNA sequence of M.meretrix tyrosinase gene(MmTyr)which encodes a protein with 689 amino acids.Sequence characteristics and phylogenetic analysis showed that there are a variety of Tyr genes in mollusks,which can be divided into different categories.The abundance of MmTyr transcript was detected in six tissues including mantle,adductor muscle,digestive gland,foot,gill and siphon of adult M.meretrix with qRT-PCR.The results showed a higher expression specifically in the mantle,digestive gland and siphon,which was consistent with the phenotypic color difference.In the embryos and larvae at different developmental stages,high expression was found in the trochophore larvae and juvenile clams.Among three M.meretrix strains with different shell colors,the expression level of MmTyr and total melanin content in the mantle edge both showed significant differences,suggesting that MmTyr is involved in the formation of shell color.The results obtained in this study will improve our understanding of molluscan tyrosinase gene function and molecular mechanism of shell color pattern determination.

Biochemical Composition and Nutritional Value of Different Shell Color Strains of Pacific Oyster Crassostrea gigas

The shell color of Pacific oyster(Crassostrea gigas) is a desirable trait; but the nutritional studies on C. gigas with different shell colors have not been conducted. Through successive selective breeding, five shell color strains of black(B), purple(P), orange(O), golden(G) and white(W) C. gigas have been developed. The aim of this study was to evaluate the chemical composition and nutritional value of five shell color strains and one commercial population with a common color. The biochemical composition including moisture, total protein, glycogen, ash, total fat, fatty acids(FA), amino acids and minerals was detected. The results indicated that the protein(50.76%–56.57%) was the major component. The content of glycogen showed a significant difference between orange shell and golden shell strains, as well as between commercial population and golden shell strain. In addition, all shell color strains contained a large amount of essential amino acids(12.20–14.15 g(100 g)^(-1)), of them leucine(2.81–3.29 g(100 g)^(-1)) and lysine(2.79–3.28 g(100 g)^(-1)) were predominant. The oysters were rich in polyunsaturated fatty acids(42.26%–45.24% of total fatty acid) with high levels of DHA(18.53%–21.16% of total fatty acid) and EPA(17.23%–18.68% of total fatty acid). Significant differences of mineral contents(Mg, Zn, Fe and Cu) were identified among the six populations. These results indicated that C. gigas with different shell colors presented rich nutritional value with high protein, glycogen, essential amino acids and polyunsaturated fatty acids. The biochemical composition obtained in this study is useful for selective breeding of C. gigas with different shell colors.

长牡蛎壳橙性状遗传参数评估及与生长性状的关联性

长牡蛎壳橙快速生长品系是结合群体选育与种内群体间杂交方法,以壳色性状和生长性状为选育指标,经过连续3代选育获得的新品系。本研究以第1代长牡蛎壳橙快速生长品系(G1)为亲本,采用巢式设计建立了48个混养家系,共获得863个个体。利用微卫星标记对混养家系进行了系谱分析,并基于REML法评估了长牡蛎壳橙快速生长品系壳色性状的遗传参数及与生长性状的相关性。结果显示,863个个体中,有851个个体被准确鉴定其所属家系;长牡蛎壳橙快速生长品系壳色性状颜色参数指标a*(红绿轴色品指数)、b*(黄蓝轴色品指数)和ΔE(色差)等均具中高等遗传力,大小依次为0.47±0.23、0.42±0.21和0.56±0.29。4个颜色参数指标间的遗传相关和表型相关范围分别为−0.79~0.86和−0.45~0.48。壳色性状与各生长性状的遗传相关和表型相关较低,分别为−0.33~0.17和−0.04~0.11。研究表明,在长牡蛎壳橙快速生长品系育种过程中,对壳色性状进行选育可以得到预期的改良效果。此外,壳橙性状与生长性状应分别作为目标性状进行协同选择,以实现同时改良两个性状的目的。本研究可为长牡蛎壳橙快速生长品系选育提供基础资料。

SLCO1C1和SLCO4C1基因与绿壳蛋鸡不同产蛋期壳色相关性研究

为探究SLCO家族基因与绿壳蛋壳色的关系,试验以产绿壳蛋母鸡为试验样本,分别收集产蛋前期(150日龄)和产蛋后期(500日龄)的鸡蛋、心脏、肝脏、脾脏、肌肉、卵巢、壳腺组织和血样样品,采用色差仪测定壳色数值;ELISA方法检测血清中血红素加氧酶1(HO-1)的含量;利用荧光定量PCR测定HO-1和SLCO家族基因的表达。结果显示:产蛋前期蛋壳L*值极显著低于产蛋后期(P<0.01),而b*值极显著高于产蛋后期(P<0.01);产蛋前期血清中HO-1含量和壳腺中HO-1表达量极显著高于产蛋后期(P<0.01);SLCO1C1和SLCO4C1在壳腺中特异性表达,SLCO1A2在肝脏中特异性表达;产蛋前期SLCO1C1和SLCO4C1 mRNA表达量显著高于产蛋后期(P<0.05)。结果表明HO-1基因表达与酶活性下降造成绿壳蛋鸡壳色变浅,SLCO1C1和SLCO4C1可能是胆绿素合成和转运的重要基因。

四角蛤蜊(Mactra veneriformis)壳色分布及贝壳金属元素含量特征分析

为了探究四角蛤蜊贝壳中颜色分布以及金属元素含量特征,本试验以天津大港和东疆港地区四角蛤蜊(Mactra veneriformis)紫色和白色壳色群体为研究对象,采用体视显微镜观察法、原子吸收光谱仪(AAS)测定法,比较分析不同壳色贝壳着色分布特点,以及2个地区紫色、白色壳色四角蛤蜊的棱柱层、珍珠层的金属元素含量组成,全面了解不同壳色群体之间金属元素含量的异同点。结果表明:四角蛤蜊紫壳群体的壳内侧比壳外侧显示出更深的紫色,紫色色素主要分布于贝壳棱柱层与角质层、棱柱层与珍珠层的交界处;Na元素和K元素在大港地区的2个壳层中,紫色群体含量均显著高于白色群体,Mg元素在2个地区2个壳层中,紫壳含量均显著高于白壳。综上,四角蛤蜊贝壳中颜色分布在壳层交界处,Mg元素可能与四角蛤蜊的紫壳形成有关。

UPLC-MS metabolomics provides insights into the diff erences between black- and white-shelled Pacifi c oysters Crassostrea gigas

A variety of shell colors are one of the most fundamental characteristics of molluscs,which have importantly ecological and economic signifi cance.The Pacifi c oyster Crassostrea gigas is distributed in many sea areas around the world and also an aquacultured mollusc with high nutritional value.In this study,the whole soft body and the mantle tissue of black-shelled Pacifi c oyster(BSO)and white-shelled Pacifi c oyster(WSO)with starkly diff erent melanin contents were compared,and the diff erences in physiology and metabolism between BSO and WSO were analyzed.The results of physiological indicators suggested BSO show more melanin,more dry matter,more crude lipid content,and stronger ability to scavenge free radicals than WSO.The altered metabolites of glycerophospholipids,fatty acyls,and steroids revealed diff erent regulatory mechanisms of lipids.The correlation analysis of metabolomics and previously published RNAseq data suggested that BSO and WSO mainly diff ered in the basal metabolic processes,such as lipid,amino acid and purine metabolisms.This study provides insights into the changes in the physiological indictors and the metabolites of oysters with varying melanin content.

2种壳色福寿螺营养成分研究

测定2种壳色(黑壳和黄壳)福寿螺肌肉的常规营养成分、脂肪酸和氨基酸组分,通过对不同组分的分析,评价其营养价值的大小。结果表明,黄壳福寿螺粗脂肪和粗灰分含量均低于黑壳福寿螺,而粗蛋白含量则高于黑壳福寿螺;2种壳色福寿螺共检测出24种脂肪酸,所含饱和脂肪酸含量均较低,二十碳五烯酸和二十二碳六烯酸总量相当;2种壳色福寿螺共检测出18种氨基酸,必需氨基酸含量均较为全面,黑壳福寿螺丝氨酸、甘氨酸、胱氨酸含量高于黄壳福寿螺,其余氨基酸含量均低于黄壳福寿螺。指出,2种福寿螺对中华绒螯蟹的氨基酸比值系数分值均>96,具有较好的蛋白质组成,营养价值较高,能够满足中华绒螯蟹对蛋白质的需求,可有条件地作为饲料蛋白源替代传统经济螺及部分鱼粉使用。

PS@SiO_(2)微球的合成及其三维光子晶体的光学性能

以乙烯基三乙氧基硅烷为硅源,通过其在碱性条件下的水解缩聚,在聚苯乙烯(PS)微球表面包覆乙烯基修饰的二氧化硅(Vi-SiO_(2))壳层制备PS@SiO_(2)微球,并通过刮涂法进一步制得PS@SiO_(2)三维光子晶体。对比了PS微球在包覆Vi-SiO_(2)前后的微观形貌、粒径和化学组成的差异,分析了PS@SiO_(2)光子晶体的形貌和光学性能。结果表明:Vi-SiO_(2)在PS微球表面形成了均匀且光滑的外壳,并且Vi-SiO_(2)的包覆对PS微球的单分散性和球形度无明显影响。由4种不同粒径的PS@SiO_(2)微球自组装的三维光子晶体都具有规则的面心立方结构,其结构色随PS@SiO_(2)微球粒径的增大发生红移,并且都具有虹彩效应。

虾夷扇贝UROS基因的全基因组鉴定、序列特征及表达分析

为探明尿卟啉原Ⅲ合酶(UROS)基因在贝类壳色形成中的分子功能,利用生物信息学和实时荧光定量PCR等方法,进行虾夷扇贝UROS基因的全基因组鉴定、序列特征及其在不同壳色个体中的表达分析。结果显示,在虾夷扇贝全基因组范围内鉴定获得1个单拷贝的UROS基因,将其命名为PyUROS基因。PyUROS基因的序列全长为68808 bp,包括9个外显子、8个内含子,共编码298个氨基酸。在PyUROS蛋白质序列中预测到1个HemD保守功能域,表明本试验中所鉴定的PyUROS基因为UROS基因。PyUROS基因在虾夷扇贝成体各组织中广泛表达,表明其在虾夷扇贝生命活动中发挥重要作用。PyUROS基因在虾夷扇贝不同外套膜区域及不同壳色个体间显著差异表达,推测其在虾夷扇贝壳色形成中发挥重要功能。本试验结果为贝类壳色形成分子机制研究提供了重要参考,为贝类壳色遗传育种工作奠定了理论基础。

莲子壳棉织物染色工艺研究

文章主要研究了莲子壳色素的水提法最佳提取工艺及对棉织物的染色性能。利用单因素试验法确定了莲子壳色素最佳的提取条件与直接染色的最佳工艺,通过测试染色棉织物K/S值,分析了不同金属媒染剂与其对应的前媒、同媒与后媒染色法的染色效果。结果表明,莲子壳色素最佳提取时间为120 min,最佳提取温度为80℃,最佳莲子壳粉末用量为5 g/50mL。在棉织物上,最佳的染色条件是:染液的浓度达到200%,温度保持在90℃,染色时间为70 min。铁离子媒染对棉织物的颜色有很大的影响,而后媒染则是对颜色深浅的影响最大的方法。所有媒染试样的干、湿摩擦、耐皂洗与耐日晒色牢度测试的数值均达到生产要求。

构建个性化BASH SHELL环境

Shell是允许Linux用户输入命令的界面.本文讨论在基于ANSI兼容终端里,通过对Shell内置的系统变量的设置,定制个性化的用户登录环境.

头盔外壳水披覆转印方法研究

产品经表面水披覆转印,其外观品质将大幅提升。然而,水披覆转印方法对于表面是平面的产品较易实现,对于表面为曲面的产品如头盔外壳的外表面,则精准实现难度较大,很容易造成缺陷,如图案比例失调、色彩变淡和残缺不全等,这些缺陷导致良品率大大降低。借助一种以填充气球作为辅助工具,采用直下拨膜转印的方法,有效解决了头盔外壳的转印难题。填充气球可以封堵头盔外壳的孔洞,避免转印过程中对图案造成扰动和破坏,填充气球内部的配重物可以确保转印入水动作顺滑,避免转印过程中产生图案波纹。直下拨膜转印方法是将工件沿铅垂方向入水,协同多方向拨膜,完成转印过程。这种新的转印方法简单易学,降低了转印难度,提高了转印合格率,不仅有效解决了头盔外壳的水披覆转印问题,也为同类产品提供了可以借鉴的工具和方法。

关于某动力舱段壳体色差问题的分析与处理

动力舱段壳体是某产品的关键零件之一,在科研试制阶段部分壳体阳极氧化后存在明显色差问题,严重影响该型产品的研制进度。针对动力舱段壳体阳极氧化色差问题,根据解剖试验结果和对铸锭加工过程的影响因素进行排查,最终确定故障原因并提出了改进措施。经验证措施有效,成功解决了动力舱段壳体阳极氧化色差问题。

不同底质环境对方斑东风螺稚螺生长、壳色及抗氧化性能的影响

为优化方斑东风螺(Babylonia areolata)健康养殖技术,比较分析了方斑东风螺稚螺在5种底质环境下(河砂、棕色陶粒、黑色陶粒、黄色陶粒、白色陶粒)的生长、壳色及抗氧化性能差异。结果表明,河砂组中底质氨氮(NH_(4)^(+)-N)质量浓度为(0.382±0.010)mg·L^(−1),显著高于其他实验组(P<0.05);棕色陶粒组的成活率最高[(62.00±2.00)%],显著高于河砂[(56.00±1.00)%]、黄色陶粒[(48.00±2.00)%]和白色陶粒[(42.50±3.00)%]组(P<0.05);河砂组和棕色陶粒组的壳高、壳宽、体质量显著高于黑色、黄色、白色陶粒组(P<0.05)。实验结束时,棕色陶粒组的壳色更艳丽,其壳色的明度值(L^(*))、红度值(a^(*))、黄度值(b^(*))皆显著高于其他实验组(P<0.05)。棕色陶粒组总抗氧化能力显著高于其他实验组,而过氧化氢酶活性和丙二醛质量摩尔浓度分别为(12.614±0.378)U·mg^(−1)和(1.179±0.001)nmol·mg^(−1),均低于其他实验组。综上所述,底质环境会显著影响方斑东风螺稚螺的生长、壳色和抗氧化性能,其中棕色陶粒较适合方斑东风螺稚螺的养殖,在生产中可以选用棕色陶粒替代河砂作为底质。

三角帆蚌Hc-GSK3β基因鉴定及内壳色性状相关SNP筛选

为了探究三角帆蚌(Hyriopsis cumingii)糖原合成激酶-3β(GSK3β)基因对壳色的影响,研究采用RACE技术获得Hc-GSK3β基因cDNA全长1867 bp,其中包含1261 bp的ORF区编码420个氨基酸,ORF中含有一个S_TKc结构域,该结构域序列高度保守。组织差异表达分析发现Hc-GSK3β基因在紫色蚌鳃、斧足、内脏团和边缘膜组织中表达量高于白色蚌的表达量(P<0.05),且在斧足和边缘膜表达差异水平达到极显著(P<0.01),而在紫色蚌闭壳肌组织中表达量显著低于白色蚌(P<0.05)。原位杂交(ISH)实验结果显示在三角帆蚌外套膜的外褶、中褶、内褶、背膜区和腹膜区均有阳性信号产生,且在外褶的信号表达较强烈。该基因经重测序比较,共鉴定出6个SNP位点,其中在C+185A位点的CA基因型在紫色蚌的分布频率显著高于白色三角帆蚌(P<0.05);在紫色蚌中,T+341G位点TT基因型三角帆蚌内壳颜色参数b值显著低于TG基因型(P<0.05)。研究表明,Hc-GSK3β基因参与了三角帆蚌壳色形成,筛选的SNP标记可用于三角帆蚌壳色育种。

三角帆蚌四个颜色选育系贝壳珍珠层颜色与外壳色的相关性分析

制片蚌珍珠层颜色是决定培育珍珠颜色的主要因素,珍珠层颜色性状已成为珍珠贝遗传改良的重要目标性状,但珍珠层颜色度量难度较大,严重降低了选育效率。本文选用12月龄红色、蓝色、金色和白色选育系三角帆蚌(Hyriopsis cumingii)幼蚌为试验材料,利用色差仪获得上述4个三角帆蚌选育系珍珠层颜色与外壳色的颜色参数L、a和b值,并对各颜色参数进行相关性分析、主成分分析和回归分析,探索珍珠层颜色与外壳色之间的相关性。结果表明:4个三角帆蚌选育系珍珠层颜色与外壳色皆显著相关(P<0.05),红色和蓝色选育系珍珠层颜色与外壳色相关性相对更强。红色和蓝色选育系珍珠层颜色的L、a和b值均分别与外壳色中至少1个颜色参数存在显著相关(P<0.05),其中红色选育系中珍珠层颜色的a值与外壳色的b值相关性最强(P<0.01),相关系数r为-0.557;蓝色选育系中珍珠层颜色与外壳色的L值相关性最强(P<0.01),相关系数r为0.533;金色选育系中外壳色的L值与珍珠层颜色的a和b值均显著相关(P<0.05),相关系数r分别为0.331和0.335;白色选育系中仅a值在珍珠层颜色与外壳色存在极显著相关(P<0.01),相关系数为0.286。本研究揭示了不同颜色选育系的三角帆蚌幼蚌珍珠层颜色与外壳色具有相关性,对指导三角帆蚌珍珠层颜色早期选育具有重要意义。