单环刺螠幼虫的体壁发生和体节形成

研究螠虫动物体壁发生和体节形成,可为阐释其早期发育机制以及体节在螠虫动物进化中的意义提供科学数据。本文以生活于沿海底质U形洞穴中的单环刺螠为材料,研究了单环刺螠幼虫的体壁发生和体节形成过程。研究显示,单环刺螠(Urechis unicinctus)担轮幼虫的体壁由单层上皮组织构成;至体节幼虫时,体壁变为单层上皮组织、结缔组织和纵向分布的肌纤维组成的多层结构,且体壁表面出现明显的分节;蠕虫状幼虫体节消失,体壁单层上皮细胞聚集形成不规则的乳突状结构,上皮中黏液细胞增多、结缔组织和肌纤维增多;至幼螠时,体壁的组织结构与成体基本一致,由复层上皮组织、结缔组织和肌肉组织(外环肌-中纵肌-内环肌)构成;单环刺螠体壁结构的不断分化,体现了其由浮游生活方式向爬行和穴居生活方式转变的适应过程。TUNEL检测发现,在单环刺螠幼虫体节发生过程中未出现明显的细胞凋亡现象。使用细胞增殖标记分子PCNA(Proliferating cell nuclear antigen)检测单环刺螠体节发生区域增殖细胞的分布时发现：在担轮幼虫中期,其后体部首先出现增殖细胞带,并在随后的发育过程中形成体节细胞增厚区;担轮幼虫晚期...     

hairy和hedgehog在单环刺蜢幼虫体节形成过程中的表达特征分析

hairy作为成对控制基因参与果蝇等体节动物的体节形成;体节极性基因hedgehog是节肢动物和环节动物体节边界维持的关键基因。本研究分析了单环刺螠hairy的序列特征以及hairy和hedgehog在其幼虫体节发生过程中的时空表达特征,结果显示:单环刺螠Hairy序列中含有保守的HLH结构域、Hairy_orange结构域和四肽WRPW;其mRNA在早期体节幼虫中的表达量显著高于晚期担轮幼虫,并且定位于每个体节的边界处。单环刺螠hedgehog mRNA在体节幼虫中的表达水平显著高于早期体节幼虫,并且呈现保守的体节边界表达特征。研究结果表明,hairy和hedgehog在单环刺螠幼虫体节中的表达图式与小头虫等典型体节动物中的表达图式基本一致。     

贻贝(Mytilus edulis)发育早期酸性和碱性磷酸酶活性

采用组织化学和分光光度技术对贻贝卵、胚胎和早期幼虫酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性进行了定位和定量研究,以探讨贝类早期发育过程中的免疫防御机制。组织化学显示,从卵细胞到D型面盘幼虫各个时期都呈ACP和AKP阳性,卵细胞中阳性颗粒较大且分布比较均匀,受精卵中央着色较深,卵裂期核区呈强阳性且大分裂球内阳性颗粒较多,原肠胚和担轮幼虫外层细胞阳性较强,面盘幼虫外套膜边缘膜、内脏团和面盘基部呈强阳性。生化测定ACP和AKP活力,均是卵细胞最低,随着发育酶活力逐步提高,其中ACP活力在受精后和囊胚期明显提高,囊胚期达到最高峰,其后又略有下降;AKP活力在卵裂期、担轮幼虫和面盘幼虫提高较大,面盘幼虫期酶活力最高。ACP和AKP可能在贻贝的发育早期抵抗病原生物侵染方面发挥重要作用。     

砗蚝(Hippopus hippopus)的人工繁育

于2016年4—9月开展了砗蚝(Hippopus hippopus)人工繁育技术研究。采用五羟色胺进行催产、促使配子排放;精卵分别收集,进行异体间受精以避免自交;受精卵经过30h孵化,选出600万D形幼虫进行培育。砗蚝的早期生活史与砗磲(Tridacna spp.)相似,经历前期面盘幼虫、中期面盘幼虫、后期面盘幼虫、足面盘幼虫、单水管稚贝、双水管稚贝、外套膜触手稚贝、幼贝等阶段。与砗磲不同的是,砗蚝怀卵量较少,但卵径较大,D型幼虫也较大,幼虫趋光性更强,壳长2.0mm以后外套膜不伸出壳缘外,幼贝贝壳形态也不同于砗磲。同砗磲幼虫一样,砗蚝幼虫需要构建虫黄藻系统之后,才能出现鳃、次生壳等,从而完成变态成为稚贝。砗蚝幼虫变态率较低,仅为1.4%。中间育成期间,丝状藻和锥形螺是稚贝培育的主要敌害,需及时清理才能确保稚幼贝正常生长发育。经过120d的精心饲育,培养出平均壳长6.3mm幼贝500余个。本研究为进一步开展砗蚝人工繁育、中间育成、增殖放流、资源修复及移植保育提供了参考。     

海蜇(Rhopilema esculenta)浮浪幼虫及早期螅状体摄食行为的研究

采用对比实验与显微观察的方法,对海蜇浮浪幼虫及早期螅状体的摄食行为进行了研究。结果表明,海蜇浮浪幼虫期不摄食外界食物;浮浪幼虫附着变态发育成海蜇螅状体1d后,开始摄食其它浮浪幼虫,螅状体发育到第3天摄食能力迅速增强,能够捕食卤虫无节幼体。海蜇早期螅状体的捕食实验结果表明,早期螅状体开始捕食主要受两方面影响,一方面是口的发育,另一方面是刺细胞的发育。     

内刺盘管虫Hydroides ezoensis(Okuda)的发育及其幼虫的附着

内刺盘管虫Hydroides ezoensis(Okuda)是我国北方沿海常见的污损性附着动物之一,它可形成密集群落附生于舰、船的底部以及海洋里各种工程的设施上,严重地损害着舰、船的使用寿命和性能。 在附着管栖多毛类发育生物学方面过去已有不少论述。如Hedley(1956、1958)对Pomaloceros钙质栖管的形成,Nott(1973)~4对Spirorbis幼虫的附     

卤虫的发育与蜕皮

我国北方孤雌生殖卤虫在盐度为60,水温为19—28℃的条件下,自卵内孵出无节幼虫长成至性成熟产仔(无节幼虫或卵),需经蜕皮12—15次,其中多数为14次,历时15—18天,随后每次产仔即行蜕皮一次,本文描述了卤虫各个不同令期发育的外部形态变化,并根据其蜕皮次数和形态特征,将卤虫的发育分为十五令(15th instar)。此外还观察到在孤雌生殖的卵中有发育成为雄性的个体。     

中国海日本刺沙蚕研究

日本刺沙蚕Neanthes japonica(Izuka)分布于我用黄海、渤海沿岸;日本的日本海和太平洋沿岸:为中国和日本的特有种。 1908年,日本饭启Izuka首次报导,,定名为日本沙蚕Nereis japonica,并对其生殖发育做了简单记述。1955年,香川义信研究了日本沙蚕成体及幼虫与盐度的关系;1962年赫列勃维奇、吴宝铃报导了我国的日本沙蚕;1964年Imajima和Hartman在“日本多毛多环虫”一书鉴定为杂色刺沙蚕Neanthes diversicolor(O.F.Muller);1972年Imajima订正为现名。     

微型藻类对太平洋牡蛎幼虫生长的影响

微型藻类的营养价值,对于确定其是否适合作为双壳类动物幼虫和稚贝发育的鲜饵料是很重要的依据。日本学者对适合作为太平洋牡蛎(Crassostrea gigas)幼虫鲜饵料的四种藻类:角刺藻(Chaetoceros gracilis)、角刺藻(C. calcitrans)、陆兹尔巴夫藻(Pavlova lutheri)和海水小球藻(Nannochloropsis oculata)进行了探讨和比较。 用上述四种藻类分别投喂太平洋牡蛎幼虫21天后发现:角刺藻(C. gracilis)、角刺藻(C.     

栉孔扇贝骨形态发生蛋白Ⅰ型受体基因的克隆及表达分析

首次在栉孔扇贝(Chlamys farreri)中克隆了骨形态发生蛋白I型受体(Bone morphogenetic protein type Ⅰ receptor,cfBMPR1)基因cDNA全长序列,该基因开放阅读框长1560bp,编码为519个氨基酸。实时荧光定量反转录PCR(real-time qRT-PCR)分析结果显示,cfBMPR1基因在栉孔扇贝受精卵、4细胞期、囊胚、原肠胚、担轮幼虫期、D型幼虫期和壳顶幼虫期等发育时期均有表达,其中胚胎时期表达量高于幼虫期,提示该基因在扇贝早期发育及幼虫形态形成过程中的重要作用;在成体组织,包括外套膜、鳃、性腺、肾、横纹肌和消化腺中也均检测到了cfBMPR1的表达,其中以性腺和横纹肌中表达量最高,暗示其参与了扇贝包括繁殖和肌肉生长发育等在内的多种生物学过程。研究结果为进一步研究TGF-β信号通路在扇贝生长发育中的功能提供了基础数据。     

凿贝才女虫形态与结构观察

应用石蜡切片和电镜技术对凿贝女虫（Polydora ciliata）的形态结构进行了详细观察,以期为多毛类分类学积累更多资料。结果显示凿贝才女虫背刚毛、腹刚毛和疣足上的刚毛围绕身体形成一个刚毛环;第五刚节刚毛变形,形成爪状结构。体表有大量腺细胞。身体结构相对简单,主要由表皮、肌肉层、消化系统组成。肌肉层发达,每一体节具...     

Comparison and history of Polydora websteri and P. haswelli (Polychaeta: Spionidae) as mud-blister worms in New Zealand shellfish

Shells of commercially valued bivalves in New Zealand, Crassostrea gigas, Perna canaliculus and Pecten novaezelandiae, are damaged by blister-causing Polydora polychaete species known to be close in morphology to the widely recorded oyster pest Polydora websteri Hartman. Recent New Zealand occurrences are here confirmed to relate to two species, P. websteri, and a second similar species, Polydora haswelli Blake & Kudenov, a new record for New Zealand, previously known only from Australia; the two species are described and compared. The worms have limited distributions, with P. websteri confirmed only for Pacific oysters (C. gigas) in northern New Zealand, although prior reports indicate it may also occur on scallops and have reached the northern South Island. Polydora haswelli has been found only in northern New Zealand, occurring on subtidal mussels and scallops and native oysters (Perna canaliculus, Pecten novaezelandiae, Ostrea chilensis), as well as co-existing with intertidal P. websteri on Pacific oysters. The worms are not present in Foveaux Strait O. chilensis beds, a major source of past oyster exports to Australia. The history of mud-blister worm outbreaks in Australasia is examined. While trans-Tasman exports of live oysters from New Zealand were commonplace during the nineteenth century, there is no evidence that mud-blister worms were present in New Zealand then. The earliest reports only date from the early 1970s and only from northern New Zealand, whereas a century earlier in the 1870s at least one of these pest worms had become widespread along eastern Australian coasts.     

Alteration of benthic communities associated with copper contamination linked to boat moorings

Although copper (Cu) is an essential element for life, leaching from boat paint can cause excess environmental loading in enclosed marinas. The effects of copper contamination on benthic macrofaunal communities were examined in three San Diego Bay marinas (America's Cup, Harbor Island West and East) in Southern California, USA. The distribution of Cu concentration in sediments exhibited a clear spatial gradient, with hotspots created by the presence of boats, which in two marinas exceeded the effect range medium (ERM). Elevated sediment Cu was associated with differences in benthic assemblages, reduced species richness and enhanced dominance in America's Cup and Harbor Island West, whereas Harbor Island East did not appear to be affected. At sites without boats there were greater abundances of some amphipods such as the species Desdimelita sp., Harpinia sp., Aoroides sp., Corophium sp., Podocerus sp., bivalves such as Lyonsia californica, Musculista senhousia, Macoma sp., and polychaetes such as Diplocirrus sp. In contrast, at sites with boats, densities of Pseudopolydora paucibranchiata, Polydora nuchalis, Euchone limnicola, Exogone lourei, Tubificoides spp. were enhanced. The limited impact on Harbor Island East suggests not only lower Cu input rates and increased water flushing and mixing, but also the presence of adequate defense mechanisms that regulate availability and mitigate toxic impacts. At all three marinas, Cu in tissues of several macrobenthic species exhibited Cu bioaccumulation above levels found in the surrounding environment. The annelids Lumbrineris sp. and Tubificoides spp., and the amphipod Desdimelita sp. contained high levels of Cu, suggesting they function as Cu bioaccumulators. The spionid polychaetes Polydora nuchalis and Pseudopolydora paucibranchiata had much lower Cu concentrations than surrounding sediments, suggesting they function as Cu bioregulators. The macrobenthic invertebrates in San Diego Bay marinas that tolerate Cu pollution (e.g. P. nuchalis, P. paucibranchiata, Euchone limnicola, Typosyllis sp., Tubificoides sp.) may function as indicators of high‐Cu conditions, whereas the presence of Cu‐sensitive species (e.g. Podocerus sp., Aoroides sp., Harpinia sp., Macoma sp., Lyonsia californica) may indicate healthier conditions (less Cu‐stressed). Parallel responses by faunas of Shelter Island Yacht Basin, also in San Diego Bay, suggest potential for development of regional Cu contamination assessment criteria, and call for functional comparisons with other marinas and coastal water bodies.     

Propagation and growth of Ponnotheres pholadis living in mantle cavity of Hiatula acuta

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Response of Acartia populations to environmental variability and effects of invasive congenerics in the estuary of Bilbao, Bay of Biscay

The effect of environmental factors (river discharge, water temperature and dissolved oxygen saturation) on the abundance and distribution of Acartia populations and the interactions between their congenerics was evaluated by means of transfer function (TF) models in the estuary of Bilbao during the period 1998–2005. The recorded species were Acartia clausi, Acartia tonsa, Acartia margalefi and Acartia discaudata. Acartia clausi dominated in the entire euhaline region of this estuary until 2003 when it was displaced from the inner part by A. tonsa. This invasive species (A. tonsa) was found for the first time in 2001 and colonized successfully the inner (salinity 30) and intermediate (salinity 33) waters of this estuary since 2003. The TF models revealed an immediate and negative effect of A. tonsa on A. clausi in the intermediate salinity (33) waters, where these species showed the highest spatial overlap. The results indicate that environmental changes from 2003 influenced the abundance of Acartia species, being unfavourable for A. clausi. The decrease of A. clausi abundance in low salinity waters was related to a significant decrease of dissolved oxygen saturation levels, whereas the increase of temperature was linked to a significant increase of A. tonsa. Acartia margalefi and A. discaudata were scarce over the entire period, but they were found to be valuable indicators of hydrological changes, which were associated to climate factors. These two latter species increased in abundance and expanded their seasonal distribution, and in the case of A. margalefi also its spatial distribution, in 2002, coinciding with the period in the time-series when autumn–winter rainfall and summer temperatures were lowest, and dissolved oxygen saturation levels were highest.     

中国近海原多甲藻的形态鉴定

原多甲藻物种的分类与鉴定是其分类学研究中最困难的一项工作。本研究通过追溯原多甲藻属的分类学历史,厘清了原多甲藻属的分类学地位,并初步鉴定出23种我国近海原多甲藻属物种,描述了每个种的形态特征以及壳板模式,本文还探讨了一些相似种的区别特征,我们得出:P. oceanicum和P. murry,P. tumidum and P. fatulipes,以及P. globules和P. majus都分别是单独的物种而并非同种异名;P. diabolum为有效拉丁名而Peridinium globosum及Peridinium longipes均为别名;至于P. punctulatum和P. subinerme的分类学关系则需进一步研究才能确定。     

三疣梭子蟹(Portunus trituberculatus)CTL基因SNP位点E4-205 C/T与抗溶藻弧菌相关性分析

C-型凝集素(C-typelectin,CTL)是甲壳类动物体液免疫中重要的免疫因子之一。但CTL基因在溶藻弧菌对三疣梭子蟹(Portunustrituberculatus)感染的过程中的表达及抗病机制尚有待进一步研究。为初步阐明CTL基因SNP E4-205 C/T位点与抗溶藻弧菌感染相关的分子机制,对不同基因型梭子蟹进行溶藻弧菌感染,通过绝对定量方法分析不同基因型梭子蟹肝胰腺、肌肉组织中溶藻弧菌的复制情况。发现溶藻弧菌感染后12 h内梭子蟹肝胰腺、肌肉组织中C/C组细菌数量显著高于T/T组,结果表明T/T组梭子蟹抗感染能力显著高于C/C组。进一步对该位点非同义突变(ACT-ATT)导致的一个氨基酸改变(Thr-Ile)的两种蛋白进行体外重组表达,并对两种重组蛋白CTL-ATT及CTL-ACT进行活性分析。发现两种重组蛋白对溶藻弧菌生长均具有一定的抑制作用, CTL-ATT的抑菌活性显著高于CTL-ACT。重组蛋白CTL-ATT与PAMPs的结合活性高于CTL-ACT与PAMPs的结合活性,同时两种蛋白与PAMPs和溶藻弧菌的结合活性具有浓度依赖性。结果表明三疣梭子蟹CTL基因参与机...     

大菱鲆(Scophthalmus maximus)、星斑川鲽(Platichthys stellatus)及其杂交种的形态学分析

利用方差分析、聚类分析、判别分析和主成分分析等多元分析方法,对大菱鲆、星斑川鲽及其杂交种(大菱鲆♀×星斑川鲽♂)的可数性状和可量性状进行了分析。结果表明:(1)可数性状中,除腹鳍鳍条数外,杂交种与母本大菱鲆差异不显著,而与父本星斑川鲽差异极显著。(2)可量性状中,杂交种和大菱鲆差异不显著的性状占可量性状的45%,而与星斑川鲽都为显著差异。可量性状的杂种指数平均值为15.56,显示杂交种可量性状总体属于偏母本。(3)聚类分析表明,杂交种与大菱鲆形态较为接近,先聚为一支,再与星斑川鲽聚为一支。(4)主成分分析表明,共获得了4个主成分,其累积总变异的贡献率为73.49%。主成分散点图表明杂交种在形态差异上独立于大菱鲆和星斑川鲽。(5)判别分析表明,利用10个对结果影响贡献率较大的参数分别构建了其判别函数,对大菱鲆、星斑川鲽和杂交种的综合判别准确率达到98.9%,判别效果非常显著。研究认为,杂交种的形态与母本比较相似,但可以通过形态判别分析将三者进行区分判别。     

长毛对虾(Penaeus penicillatus)SNP标记开发及亲子鉴定技术研究

长毛对虾是我国南方沿海地区的重要经济虾类。近年来,由于过度捕捞、病害频发以及海洋环境恶化,长毛对虾的自然资源量大幅减少。为补充自然资源,改善种群结构,1980年我国开始对长毛对虾开展增殖放流工作。然而,增殖放流的效果如何,目前尚缺乏有效的评估手段。以长毛对虾为实验材料,通过对其基因组进行de novo测序和重测序开发SNP (single nucleotide polymorphism)标记,最终建立长毛对虾的亲子鉴定技术。具体研究结果如下:长毛对虾基因组大小为1 335.76 Mb GC (guanine cytosine)含量为40.86%,N50为1 221 bp;以组装的长毛对虾基因组为参考基因组通过重测序进行SNP挖掘,共获得12 579 780个原始SNP位点,经筛选,优化及模型选择,最终建立了基于192个SNP标记的长毛对虾亲子鉴定技术,亲子鉴定成功率为100%(95%的置信度)。研究结果可为下一步长毛对虾增殖放流效果评估提供参考。     

Molecular identification of bloom-forming species Phaeocystis globosa (Pryninesiophyta) and its dispersal based on rDNA ITS sequence analysis

The colony-forming Phaeocystis species are causative agents of dense bloom occurrences in coastal waters worldwide. It is difficult to separate them because of the different morphologies associated with their colonial stages. In this study we applied molecular approaches to analyze the genetic variation of Phaeocystis globosa and Phaeocystis pouchetii from several geographic regions, and to assist in tracing the dispersal of bloom-forming Phaeocystis species in coastal waters of China. The sequences of the internal transcribed spacers (ITS1 and ITS2) of rDNA and the 5.8S ribosomal RNA gene of Phaeocystis strains were determined. Sequence comparison shows that P.globosa was the most divergent to P. pouchetii, exhibiting sequence divergence higher than 0.08. However, lower genetic divergences existed between strains of P.globosa. The sequence comparison of the Phaeocystis rDNA ITS clearly shows that the species isolated from the southeast coast of China is identified as P.globosa rather than P. cf. pouchetii or other species. Furthermore, the significance of rDNA variation in distinct global populations of P.globosa suggested it might have had sufficient time to accumulate detectable mutations at the rDNA locus, supporting the hypothesis of ancient dispersal of P.globosa to many areas, meaning that P.globosa blooms in the coastal waters of China are endemic rather than a newly introduced species or a foreign source. Finally, based on the high divergent region of rDNA ITS, a pair of species-specific primers for P.globosa were designed, they could be useful to detect the presence of this species in mixed plankton assemblages or flagellate stages that are recognized with diffculties by means of conventional microscopy.