藤壶幼虫附着的分子机理研究进展：转录组和蛋白质组

藤壶是一种重要的海洋污损生物,其在海洋工程设备表面的附着严重地影响着设备的使用,造成巨大的经济损失。发展环境友好的藤壶防除技术离不开对藤壶附着机理的深刻理解,而目前对于藤壶附着变态过程的调控机理尚未研究清楚。藤壶幼虫的附着涉及幼虫的生长发育、基底的探索、变态过程以及藤壶胶的分泌等多个复杂过程,传统的细胞生物学和分子生物学方法难以对这些过程进行详尽的分析。近年来,基于高通量测序技术的转录组学和蛋白质组学成为研究污损生物附着过程的重要手段,在揭示藤壶幼虫附着机理方面积累了大量的数据。本文综述了近年来国内外对于藤壶附着机理的研究,总结了利用组学方法研究藤壶幼虫的附着和变态过程、藤壶胶的成分和固化机理方面的研究进展,对未来防污技术的研究方向提出建议。     

几种阳离子对葡萄牙牡蛎幼虫附着和变态的影响

葡萄牙牡蛎眼点幼虫暴露于K+、Ca2+、Mg2+、NH4+不同添加浓度的海水溶液中.结果显示:在最初4h内K+和NH4+可明显诱导幼虫的附着行为;7d后,10 mM和20 mM的K+以及10 ～ 25 mM的Ca2+可显著诱导幼虫的附着变态,Mg2+与对照组相比无效,NH4+造成幼虫高死亡率.这表明K+、Ca2+可能成为葡萄牙牡蛎育苗生产上幼虫附着变态的有效诱导剂.     

关于藤壶Ⅱ期无节幼虫的饵料效果

本文叙述了藤壶Ⅱ期无节幼虫对星点东方饨仔稚鱼的饵料效果的实验结果。单独投与藤壶Ⅱ期无节幼虫时，其饵料效果不太好。而当藤壶Ⅱ期无节幼虫与其他饵料生物混合投饵时，效果较好，特别是与盐水丰年虫一起投饵，可得到更好的结果。     

扇贝幼虫附着基的细菌组成及其作用

自海湾扇贝幼虫附着基表面分离到99株附着细菌。经鉴定、分类至9属包括弧菌属、假单胞菌属、无色杆菌属,芽孢杆菌属、气单胞菌属、葡萄球菌属、微球菌属、棒杆菌属和黄杆菌属。扇贝幼虫的附着基表面具有一定数量的附着细菌。单一菌株菌膜实验表明,不同菌株形成的菌膜对幼虫附着的吸引力大小不一。有的细菌促进幼虫附着,有的却有抑制作用。     

化学物质诱导九孔鲍幼虫变态附着的初步研究

用KCl、尿素[CO(NH2)2]、乙二胺四乙酸二钠(EDTA-Na2)诱导九孔鲍幼虫变态附着,分析同种化学物质的不同质量浓度以及不同的化学物质对变态附着的影响,并对他们的诱导效果进行了对比.试验结果表明,质量浓度为0.075 g/L的KCl和0.35 g/L 的EDTA-Na2的诱导作用最显著,而尿素的诱导效果较差,尿素诱导九孔鲍幼虫变态附着的最佳质量浓度是0.1 g/L.不同的诱导物及同一种诱导物在不同的质量浓度下对九孔鲍幼虫变态附着的诱导作用有较大的差异.     

5-羟色胺诱导刺参幼虫附着变态

采用不同浓度的5-羟色胺（5-HT）溶液诱导刺参幼虫附着变态,处理不同时间后,计算附着变态率。结果表明：使用浓度为0．001、0．01、0．1和1mmol／L的5-HT溶液诱导刺参幼虫12和24小时均可不同程度地提高刺参幼虫附着变态率。以浓度为0．1mmol／L的5-HT溶液诱导刺参幼虫24小时效果最好,附着变态率提高12．8％。     

化学物质诱导泥蚶幼虫附着变态的研究↑（*）

1996年8～9月间在室内用8种化学诱导物对泥蚶变态前期幼虫进行附着变态诱导实验。结果表明,8种药物对泥蚶幼虫的变态均有一定的诱导作用。其中,3-HT、EPI和NE对幼虫变态的诱导作用极显著,有效浓度范围较广;KCl和Ala的诱导作用较显著,有效浓度范围较窄;而Try、CABA和Ach只有某些浓度组的诱导效果明显,诱导效率对浓度的信赖性较强。从诱导物浓度来看,10-4mol/L的Ala、GABA和10-5mol/L的EPI诱导效果最好,与对照组相比,变态率均提高12%以上。不同处理时间试验表明,处理时间的长短与幼虫的变态率无一致的相关性关系,因药而异;总的来看,处理时间不超过8h的诱导效果较好,时间过长诱导率降低(GABA除外)。其中,用10-5mol/L的Ala处理1～4h或10-5mol/L的EPI处理4h效果最好,与对照组相比,变态率均提高25%以上。8种药物中,只有Try表现出对幼虫明显的毒性影响,Try的浓度越高,处理时间越长,幼虫的死亡率越高,用10-4mol/L的Try处理幼虫3h,死亡率达89%。     

GABA受体拮抗剂荷包牡丹碱和CGP52432对厚壳贻贝幼虫附着变态的影响

为研究GABA及其受体拮抗剂荷包牡丹碱（GABA_A受体）和CGP52432 （GABA_B受体）在厚壳贻贝幼虫附着变态中的调控作用,实验通过分析厚壳贻贝不同发育阶段幼虫转录组数据获得GABA受体相关蛋白基因（GABARAP）和GABA_B2受体基因(GABA_B2R),发现GABA_B2R在变态前期的眼点幼虫阶段相较于其他阶段幼体显著高表达。通过实时荧光定量PCR验证也得到相似的表达模式,显示GABA_B2R可能参与调控厚壳贻贝幼虫变态发育。药理学实验结果显示,10^-4 mol/L GABA对厚壳贻贝幼虫的变态具有诱导活性（27.2%±3.0%）。在拮抗剂实验中,10^-6～10^-4 mol/L荷包牡丹碱和CGP52432均显著抑制了厚壳贻贝幼虫变态,且抑制作用随浓度升高而增强。实验还发现GABA及其受体拮抗剂都抑制了厚壳贻贝幼虫的游泳行为。研究表明,GABA_A或GABA_...     

西施舌(Coelomactra antiquata)幼虫附着变态及胚后发育的研究

在1999-2011年间,为了充实西施舌(Coelomactra antiquate)幼虫附着变态生物学理论基础和提高育苗成苗率,采取显微连续观察和活体显微摄影方法,对西施舌的幼虫发育各阶段的形态特征、附着变态及胚后发育的全过程等进行研究。结果表明,西施舌的直线铰合幼虫出现前闭壳肌和3对面盘收缩肌。壳顶幼虫时期开始生成后闭壳肌。足呈舌状,足神经节上方有一对平衡器,面盘中央具顶鞭毛朿。后期壳顶幼虫出现足丝腺、管状内鳃丝。匍匐幼虫足呈棒状,匍匐活动频繁,足丝腺发达,内鳃丝2~3对。面盘萎缩,顶鞭毛朿脱落,开始分泌足丝附着;次生壳生成;器官移位,唇瓣、口、内鳃相连接,以鳃滤食为西施舌幼虫变态的主要生物学标志。初期稚贝唇瓣二指形,内鳃丝2~4对。初期幼贝唇瓣三角形,眼点消失,外鳃丝生成,除性腺外,内部器官发育齐全。此项研究,对于进行西施舌幼虫的诱导附着及完善其产业化育苗工艺都具有重要意义。     

Larval rearing of the giant Azorean barnacle,Megabalanus azoricus (Pilsbry, 1916): feeding trials,larval development and settlement on artificial substrata

A series of experiments were conducted to obtain an efficient larval rearing protocol for Megabalanus azoricus. The first part of this study investigates the effect of microalgae‐based diets on survival and larval development. Mono and mixed‐diets were tested at 20 ± 1°C, in a sequence of 11‐day feeding experiments. The second part presents a preliminary study on the influence of a biofilm on recruitment and use of oyster spat collectors in a mass rearing system. A photographic record of larval development and a brief reference to the diagnostic features that enable quick larval staging are also presented, along with morphometric measurements. Of the microalgae tested (Chaetoceros sp., Chloromonas sp., Dunaliella sp., T‐Isochrysis sp. and Skeletonema sp.) the mixed‐diet Skeletonema sp. with T‐Isocrysis sp. showed the highest survival percentages: total survival ranged from 79.7 to 85.7% and 69.7–80.0% of nauplii were in stage VI after 11 days of rearing. Cypris were also present, but only represented 5.3% of the survivors at most. In the mass rearing system juveniles were found settled in the collectors after 25 days, at 20 ± 1°C. However recruitment was less than 1%. Preliminary results showed no settlement preference towards collectors with biofilm. Nevertheless, this study provides the first record of M. azoricus settlement under laboratorial conditions and represent a starting point for future larval rearing studies.     

The effect of environment on puerulus settlement of the western rock lobster (PanuUrus cygnus) in Western Australia

The level of puerulus settlement has proven to be a reliable predictor of the recruitment to the western rock lobster (Panulirus cygnus) fishery three and four years later. It is generally accepted that the early larval stages are moved offshore by wind-driven surface currents. Previous studies have shown that coastal sea level, used as an indicator of the strength of the Leeuwin Current flowing down the west coast of Australia, was positively related to the level of puerulus settling on the inshore reefs after a 9- to 11-month larval life. In this paper a significant relationship is also demonstrated between winter/spring storms, which are usually associated with onshore westerly winds, and the level of puerulus settlement (multiple correlation of 0.83, R¹= 0.68, n = 22). Rainfall from coastal localities was used as an index of the storms. The residuals from this relationship showed a significant positive autocorrelation. The autocorrelation was incorporated into the relationship by using time series analysis with a transfer function model and a first-order autocorrelation (R²= 0.76). The possible relationship between storms and the Leeuwin Current and their effect on the puerulus settlement are considered, and the potential for the environmental variables to bias or obscure the spawning stock recruitment relationship is discussed.     

Effect of temperature on the development, growth, survival and settlement of green mussel Perna viridis (Linnaeus, 1758)

The effect of temperature on the development, growth, survival and settlement of Perna viridis was studied under controlled conditions to provide information needed for the development of commercial hatchery technology for green mussel P. viridis. Total mortality of the larvae occurred after 24 h at temperatures of 33°C and 35°C. At 24°C, larvae took longer to settle than at temperatures of 27°C, 29°C and 31°C. For optimum larval development (8–13 h), growth (17.2±0.84 μm day^–1) and survival (55.2±0.84%), a hatchery rearing temperature of 31°C is required. For settlement no significant difference was seen between the percentage settlement at 29°C (49.3±3.34%) and 31°C (45.8±1.76%). However, the process of settlement began and ended earlier at 29°C (from 15 to 18 days) than at 31°C (from 18 to 20 days). Thus for larval settlement a temperature of 29°C is recommended.     

The effects of temperature on growth,development and settlement of northern rock sole larvae (Lepidopsetta polyxystra)

Northern rock sole (Lepidopsetta polyxystra) is a commercially important fish in the North Pacific and a focal species in understanding larval transport to nursery grounds in the Bering Sea. However, the temperature‐dependent vital rates and settlement dynamics for this species have not been described in detail. We reared northern rock sole larvae in the laboratory to measure growth, condition, development and settlement parameters across four temperatures (2, 4, 7 and 10°C). Both length and mass‐measured growth rates increased with temperature and were best described by non‐linear regression. Residuals of the length–mass relationships were positively related to temperature, indicating larval condition also increased with temperature. Larval development and settlement were largely size dependent, resulting in reduced larval stage duration and earlier settlement at higher temperatures owing to more rapid growth at elevated temperatures. However, larvae at colder temperatures were less developed at a given size, but more likely to settle at smaller sizes than larvae reared in warmer conditions. These temperature–response parameters can be used to refine current and future transport models for northern rock sole larvae under changing environmental conditions in the North Pacific.     

The effect of vitamin E on the serum complement activity of the rainbow trout, Oncorhynchus mykiss (Walbaum)

Rainbow trout were fed three experimental diets with varying levels of vitamin E (α‐tocopherol) supplementation (0, 100 and 1000 mg kg^?1 diet), and the effects of feeding these diets on serum spontaneous haemolytic activity and classical complement activity were investigated. Hepatic α‐tocopherol levels reflected the dietary intake of the vitamin. Fish fed the diet deficient in vitamin E showed reduced growth and increased mortality. Their hepatosomatic index and erythrocyte fragility was significantly higher than both the supplemented groups and haematocrit, and complement activity were all significantly lower. There appeared to be some enhancement of serum complement activity correlated with increased dietary supplementation with vitamin E but the benefits of supplementation at levels above those currently recommended were not established.     

饲料蛋白质含量和n-3HUFA水平对大菱鲆亲鱼产卵的影响

给大菱鲆亲鱼投喂高蛋白和高水平 n 3HUFA的饲料。结果表明,与投喂低蛋白和低水平 n 3HUFA饲料组相比,大菱鲆亲鱼繁殖力明显提高。高水平试验组,亲鱼体重增重大,产卵量高、所产卵子卵径大,受精后上浮率、孵化率高,仔稚鱼的存活力强。其中卵子脂肪酸含量受亲鱼所摄饲料中脂肪酸含量的影响较大。当亲鱼组投喂试验组饲料的蛋白质为 49 3%、脂类含量为14 6%,其中∑n 3HUFA的比例为 29 3%时,平均每尾亲鱼的产卵量为 1 45×106,所产卵子的卵径为1 053 mm,卵子脂类∑n 3HUFA的比例为20 38%,浮性卵率为95%。经过30 d的饲育,大菱鲆苗种的存活率为 23%,明显高于低蛋白和低脂肪酸试验组的数据。本研究认为,大菱鲆亲鱼培育的饲料中适宜蛋白质含量应≥45%;脂类的适宜含量为≥10%,其中∑n 3HUFA的适宜比例≥20%。     

阿克苏河叶尔羌高原鳅Triplophysa(Hedinichthgs)yarkandensis(Day)生物学研究

本对阿克苏河叶尔羌高原鳅的形态特征、群体结构、繁殖、食性等生物学进行了研究。叶尔羌高原鳅体长分布在3．0～15．0cm之间，体重分布在1～33g之间。W=0．039748L^263049.Fulton肥满度雌体平均为1．54，雄体平均为1．46；Clark肥满度雌体平均为1．25，雄体平均1．16。雌体成熟个体最小体长为6．6cm，体重为5．5g，平均绝对怀卵量11543粒／尾。食性以底栖动物、水生昆虫以及鱼类幼体为主。     

The settlement and reproductive success of Lepeophtheirus salmonis (Krøyer 1837; Copepoda: Caligidae) on atypical hosts

The reproductive success of Lepeophtheirus salmonis settled on host and non‐host fish has been compared. Triplicate single species tanks of Atlantic salmon, marine three‐spined sticklebacks, saithe and Atlantic cod were exposed to 10 adult female L. salmonis per tank (n=30 lice per species). Adult female L. salmonis settlement and egg string production occurred only on salmon and cod, with no egg production occurring on saithe and three‐spined sticklebacks. The number of eggs in egg strings, hatching success of eggs and the survival of all larval stages to the copepodid stage were severely affected by the species of fish on which female L. salmonis had settled. L. salmonis settled on cod produced significantly fewer eggs, lower hatching rates and lower survival rates of larvae than females on Atlantic salmon. The production of egg strings by L. salmonis females infecting cod, which successfully hatch and moult through to the infective copepodid stage, albeit in small numbers, is discussed in terms of the implications to aquaculture and salmon and cod farming scenarios.     

Impact of wind stress anomalies on the seasonal pattern of southern rock lobster (Jasus edwardsii) settlement in South Australia

Quantified estimates of southern rock lobster (Jasus edwardii) puerulus settlement have been undertaken in the Southern Zone fishery of South Australia since the early 1990s. An analysis of mean monthly puerulus settlement indices from 1995 to 2007 in three monitoring sites revealed a strong seasonal correlation (r > 0.94 between sites) in settlement patterns. Settlement was highest during the winter months of June, July and August with peak settlement in all sites occurring in July. A reduced secondary settlement occurred during February and March. Seasonal trends were correlated with monthly wind stress and direction data in order to investigate possible environmental drivers of settlement. Using monthly averages of wind stress, it was hypothesized that strong along‐shore wind‐stress anomalies (ASWSA) prior to peak settlement would influence puerulus indices. Maximum ASWSA over the December–May period prior to maximum settlement was therefore examined. The results showed significant correlations (P < 0.1, r = 0.51–0.90) between wind stress and puerulus settlement in all but one site. We suggest that storm events, in combination with onshore surface drift during the period of settlement, are the principal physical oceanographic mechanisms influencing settlement patterns within the Southern Zone rock lobster fishery of South Australia.