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1.
肠道和肝胰腺是中华绒螯蟹(Eriocheir sinensis)重要的消化器官,本文运用组织学技术测量了中肠和后肠长度,并对肠道长与体长进行相关性分析。应用免疫组化技术对5-HT和5-HT受体2进行组织定位和计数。结果表明:(1)中华绒螯蟹的肠道长与体长接近,两者之间呈极显著正相关(P0.01)。后肠长度约为中肠的2倍;(2)5-HT和5-HT受体2在中肠和后肠中的组织定位和数量相似,均分布于黏膜上皮细胞间和肌层与外膜交界处,亦见于后肠的固有膜和黏膜下层与肌层交界处,在肠球外膜中也有大量分布;(3)5-HT和5-HT受体2阳性物质在肝胰腺的四种细胞的胞核中均有分布,在F细胞的胞质中也有分布。5-HT和5-HT受体2在中华绒螯蟹肠道和肝胰腺组织中的分布规律一致,表明中华绒螯蟹消化道5-HT发挥生理功能可能与5-HT受体2有关。此外,5-HT和5-HT受体2在后肠近肌细胞分布的特点可能与肠道收缩有关。后肠在中华绒螯蟹消化生理中的作用应引起重视。  相似文献   

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3.
为了解鲽形目Pleuronectiformes鲆科Bothidae长臂缨鲆Crossorhombus kobensis (Jordan & Starks, 1906) 核糖体RNA基因的序列多态性特征, 本研究共获得该鱼类包括18S、5.8S、ITS1和ITS2全长及28S部分序列的128条克隆序列。经序列比对、聚类分析以及重组检测, 结果显示5.8S (158bp) 无长度变异, 而其他4个基因片段则表现出较高的长度多态性, 并可分为不同序列类型: 18S (1856~1893 bp) 有4种序列类型A、B、C和R; 28S (967~974bp) 和ITS1 (407~ 505bp) 均有3种类型A、B和R; ITS2 (423~447 bp)存在2种类型A和B。此外5个基因片段在碱基组成中均表现出GC偏倚, 并且ITS2 (71.14%)>ITS1 (65.37%)>28S (62.22%)>5.8S (57.67%)>18S (54.95%)。对具有不同序列类型的18S、28S和ITS进行真、假基因推断时, 通常的判别特征不足以提供有力依据, 因此增加了与4种鲆科近缘鱼类长冠羊舌鲆Arnoglossus macrolophus、青缨鲆Crossorhombus azureus、大鳞短额鲆Engyprosopon grandisquama以及冠毛鲆Lophonectes gallus相应基因片段的比对。各基因片段的插入/缺失以及特异性碱基差异位点比对结果显示: 18S和28S的短序列类型A与4种鲆科鱼类序列一致, 而其他序列类型则不同; ITS1序列类型A与4种鲆科鱼类在类型B的缺失位点均无缺失, 因此推测18S、28S和ITS1的A类型为真基因, 而其他类型为假基因。ITS2的A和B类型在差异位点上与4个鲆科鱼类不存在一致性, 没有足够的依据对两个类型做出真、假基因的推断。长臂缨鲆核糖体RNA基因中, 5.8S序列最为保守遵循协同进化的方式, 而其他4个基因片段为非协同进化的方式。  相似文献   

4.
闫晗  惠敏  沙忠利  程娇 《海洋与湖沼》2023,54(5):1463-1475
劳盆拟刺铠虾(Munidopsis lauensis)是一种十足目铠甲虾, 能够适应深海化能合成生态系统的极端环境, 但是其已知基因序列信息却很少。为此, 采用PacBio平台的SMRT测序技术对来自南海台西南冷泉劳盆拟刺铠虾的肝胰腺、鳃、肌肉和肠混合组织进行了三代全长转录组测序。通过聚类、校正、去冗余之后共获得28 811条高质量isoform, 平均长度为2 086 bp, N50长度为2 275 bp。使用Nr、SwissPort、KEGG、KOG数据库对转录本序列进行功能注释, 共有20 616 (71.56%)条isoform得到注释。进一步高级注释共获得21 848个蛋白编码序列, 共预测到537个转录因子、6 430个长链非编码RNA和10 060个SSRs位点。KEGG通路分析发现两条可能与劳盆拟刺铠虾适应深海化能极端生境相关的通路, 分别为过氧化物酶体通路和谷胱甘肽代谢通路。其中, 共有180条isoform被发现参与编码过氧化物酶体通路中的31个关键酶, 213条isoform参与谷胱甘肽代谢通路中19个关键酶的编码。基于全长转录组数据, 利用同源比对、功能结构域预测及系统发育树构建等方法对劳盆拟刺铠虾谷胱甘肽S-转移酶(GST)基因家族进行挖掘与鉴定, 共发现属于theta、delta、mu、kappa四种亚家族的20条GST候选序列。通过对劳盆拟刺铠虾全长转录组测序、功能注释和环境适应相关的重要基因及通路的分析, 不仅丰富了深海组学数据资源, 也为进一步揭示甲壳动物适应深海化能极端环境的分子机制奠定了基础。  相似文献   

5.
The reversibility of the temperature effect on the chemical composition of interstitial waters of three deep-sea sediment samples was examined between 2 and 25°C for Cl, Na, K, Mg, Ca, Si, B, Mn and alkalinity. When the temperature of sediment samples was returned from 25°C to the initial value of 2°C, most chemical species gave nearly their initial concentrations. However, for alkalinity and in one case for magnesium, it took another three to four hours to reach their initial concentrations.  相似文献   

6.
Species compositions of deep-sea demersal fishes were compared during the day and at night in two cruises of KT-01-8 and KT-02-5. A total of 742 individuals belonging to 28 species were collected in four day and four night hauls in KT-01-8, and in KT-02- 5 128 individuals belonging to 33 species were sampled in three night and four day hauls. Principal Component Analysis (PCA) revealed that there were two distinct groups corresponding to sampling time in both cruises, although in KT-02-5 the species composition from the first haul sampled after sunrise was similar to those found in night hauls. This suggests that the species composition of deep-sea demersal fishes changes between day and night. The existence of a time lag between the sea surface and the sea floor was also suggested, lag being 2–4 hr at 500 m depths in the study area. There may be two possible explanations for the change in deep-sea demersal fish composition between daytime and nighttime: the artificial effect of successive sampling design, and actual fish migration. Since the artificial effect would not be sufficient to explain the change of demersal fish composition, the vertical or horizontal movements of deep-sea demersal fishes would contribute to the faunal change between daytime and nighttime in the study areas.  相似文献   

7.
Dead specimens of a minute fusiform rotaliid foraminifer are common in the 28–63 μm fraction of multiple corer samples from a 4850 m-deep site on the Porcupine Abyssal Plain (PAP). Their test morphology is remarkably similar to small specimens of Stainforthia fusiformis (Williamson, 1858), a species which is well known from coastal settings (intertidal to outer shelf) around NW Europe and North America. A detailed comparison of the PAP form with typical individuals of S. fusiformis from Norwegian waters (55–203 m depth), however, reveals slight but consistent morphological differences. The PAP specimens are smaller (test length 40–140 μm) than those from Norway (test length 80–380 μm), the chambers tend to be rather less elongate, the density of pores in the test wall is much lower, and there are differences in apertural features. We therefore conclude that the diminutive abyssal form is a distinct species, here referred to as Stainforthia sp. This interpretation is consistent with increasing evidence for genetic differentiation in deep-sea organisms, particularly along bathymetric gradients. Stainforthia sp. was previously illustrated by Pawlowski as Fursenkoina sp. and appears to be widespread and abundant in the abyssal North Atlantic (>4000 m depth). Stainforthia fusiformis, on the other hand, is most abundant in continental shelf and coastal settings. It extends onto the continental slope in the North Atlantic but has not been reported reliably from depths greater than about 2500 m.We suggest that the striking morphological convergence between these two species reflects the adoption of similar ecological strategies in widely separated habitats. Both are enrichment opportunists, a life-style which may explain the rather broad bathymetric range of Stainforthia fusiformis. This is a dominant species in organically-enriched and sometimes extremely oxygen-depleted environments on the continental shelf, and is a rapid coloniser of formerly azoic habitats. Live specimens of the abyssal form are typically found embedded within phytodetrital aggregates (organic material derived from primary production in the euphotic zone). It is presumably the availability of these organic-rich microhabitats, which enables this species to survive in the otherwise oligotrophic deep sea.  相似文献   

8.
海桑属红树植物遗传多样性和引种关系研究   总被引:8,自引:2,他引:8  
周涵韬  林鹏 《海洋学报》2002,24(5):98-106
以海南东寨港红树林自然保护区内无瓣海桑(Sonneratia apetala)、海南海桑(S.hainanensis)、拟海桑(S.paracaseolaris)、杯萼海桑(S.abla)、大叶海桑(S.ovata)、海桑(S.caseolaris)等6种海桑属红树植物为材料,对15个有效引物进行RAPD分析,共扩增出512条带,其中多态性条带为297,占总扩增条带的58.01%.Nei指数法分析和UPGMA统计分析表明,6种海桑属红树植物分为A,B,C3个组,平均遗传距离为0.38.A组包括无瓣海桑、海南海桑、大叶海桑、怀萼海桑,其中无瓣海桑、海南海桑、大叶海桑处于同一个亚组.B组包括拟海桑.C组包括海桑.对海南和福建无瓣海桑种群进行RAPD分析.对Shannon表型多样性指数统计结果表明,福建种群为0.669,海南种群为0.671,各种群遗传变异较大,这与无瓣海桑种群广泛的适应性相一致.对种群间的Shannon表型多样性指数分析表明,种群内的遗传变异占整个遗传变异的93.3%,而种群间的遗传变异仅占6.7%.这表明无瓣海桑种群的大部分遗传变异存在于种群内,而种群间的遗传变异较小.由此可见,无瓣海桑基因组丰富的多样性,是使其由海南成功引种到福建的重要因素.  相似文献   

9.
Our knowledge of deep-sea biodiversity is based almost entirely on morphological distinctions at the species level. Here, we use haplotype variations in the mitochondrial 16S ribosomal gene to assess biodiversity at the genome level in four deep-sea molluscan morphospecies. Genetic divergence levels among populations of the morphospecies fall within the range of interspecific divergence found in coastal marine and aquatic molluscan genera. Results indicate a rich population structure at the genetic level in deep-sea mollusks, and suggest the possibility that some seemingly coherent morphospecies are composed of cryptic species.  相似文献   

10.
利用rDNA和ITS序列对1株裸甲藻的初步鉴定   总被引:5,自引:1,他引:5  
测定了 1株分离自青岛胶州湾海水样品、从形态上初步确定为裸甲藻属 (Gymnodiniumsp,编号为 GYN- 1 5)的核糖体基因 (r DNA)和转录单元内间隔区 (Internal Transcribed Spacer,ITS)序列 ,并利用该序列对该藻进行了初步鉴定。测定的序列长 2 658bp,涵盖了小亚基 (smallsubunit,SSU) r DNA基因 3'端 1 747bp,ITS1 - 5.8S r DNA- ITS2全长和大亚基 (large subunit,LSU) r DNA基因 5'端 337bp。同源性分析该序列发现 GYN- 1 5与共生甲藻属 (Symbiodinium)中的 2个种 (Symbiodinium californium和 Gymnodinium varians)的对应序列具有很高的相似性 ;3株藻的各段 r DNA和 ITS序列的相似性均为 99%以上 ;以 SSU r DNA序列中的 3个可变区 (V1 V2 V3)和邻接法构建的系统树表明 ,GYN- 1 5与 S.californium和 G.varians构成 1个独立的新的子类群 ,该子类群属于共生甲藻属 ,而与各种裸甲藻的亲缘关系较远。根据这些结果可将GYN- 1 5初步鉴定为属于共生甲藻属。鉴于 GYN- 1 5和其它 2个种所构成的分支明显与 5个已知的子类群 (A,B,C,D,E)不同 ,因此将该分支命名为子类群 F。  相似文献   

11.
张玥  高菲  许强 《海洋通报》2021,40(2):198-205
花刺参(Stichopus monotuberculatus)是中国热带海参中具有较高经济价值的可食用海参之一.本文以花刺参幼参为实验对象,主要研究其摄食器官触手的形态特征与消化器官肠道不同区段的组织结构.结果 显示,花刺参的口周围共有20个等长的触手,每个触手由柄部和楣状触手组成.檐状触手向外张开呈掌状,从掌心中央向...  相似文献   

12.
Macrobenthos were investigated at 77 stations on the level bottom of Maizuru Bay in the spring season in 1971. Among the animals collected in this survey, two animal groups,i.e. bivalves and polychaetes, predominated.Theora lubrica was the most predominant species, occupying 39 % of the total individuals collected. An apodan holothurian,Notomastus sp.,Prionospio ehlcrsi andLumbrineris longifolia also prevailed in number.According to the similarity of the composition of eight species common in the present area, the sampling stations were classified into four categories. As the stations belonging to each category are distributed in a peculiar portion of the bay, the bay can be divided into four areas, A–D, which are characterized as follows: Area A,Theora lubrica is highly predominant; Area B, an apodan holothurian and six common polychaetes (Notomastus sp.,Lumbrineris longifolia, Paraprionospio pinnata, Glycera chirori, Tharyx sp. andPolycirrus sp.) are relatively abundant; Area C, intermediate between Areas A and B; Area D, the above-mentioned eight species are scanty. These regional divisions of the bay correspond well with those based on the physico-chemical conditions on the bottom. Benthic feature of each area of the bay was discussed in connection with the bottom environment.Comparison of the present results with the previous data has revealed a considerable decrease of population density during the past 25 years in the area concerned.  相似文献   

13.
Although a great amount of information is available on bacteria inhabiting deep-sea sediments, the occurrence of fungi in this environment has been poorly studied and documented. We report here the occurrence of fungi in deep-sea sediments from ∼5000 m depth in the Central Indian Basin (9–16°S and 73–76°E). A total of 181 cultures of fungi, most of which belong to terrestrial sporulating species, were isolated by a variety of isolation techniques. Species of Aspergillus and non-sporulating fungi were the most common. Several yeasts were also isolated. Maximum species diversity was observed in 0–2 cm sections of the sediment cores. Direct staining of the sediments with Calcofluor, a fluorescent optical brightener, revealed the presence of fungal hyphae in the sediments. Immunofluorescence using polyclonal antibodies raised against a deep-sea isolate of Aspergillus terreus (# A 4634) confirmed its presence in the form of hyphae in the sub-section from which it was isolated. A total of 25 representative species of fungi produced substantial biomass at 200 bar pressure at 30° as well as at 5 °C. Many fungi showed abnormal morphology at 200 bar/5 °C. A comparison of terrestrial isolates with several deep-sea isolates indicated that the former could grow at 200 bar pressure when growth was initiated with mycelial inocula. However, spores of a deep-sea isolate A. terreus (# A 4634), but not the terrestrial ones, showed germination at 200 bar pressure and 30 °C. Our results suggest that terrestrial species of fungi transported to the deep sea are initially stressed but may gradually adapt themselves for growth under these conditions.  相似文献   

14.
GATA家族是经典的转录因子家族,因其能特异性的与核苷酸序列T/A(GATA)A/G结合而得名。前期研究在单环刺螠(Urechis unicinctus)中筛选到GATA家族成员GATA B2与硫代谢关键酶硫醌氧化还原酶(Sulfide quinone oxidoreductase,sqr)启动子高转录活性区相互作用。为了进一步研究其是否参与硫化物代谢过程,本文鉴定了单环刺螠GATA B2基因(UuGATA B2),并分析其在成体各组织和硫化物暴露后的表达特征。结果显示:单环刺螠GATA B2的ORF全长为1788 bp,编码585个氨基酸;该氨基酸序列包含2个GATA家族保守的锌指结构域;系统进化分析显示UuGATA B2先与小头虫的GATA B2聚类,再与其它GATA4/5/6亚家族成员聚类。随后制备UuGATA B2多克隆抗体,利用Western blotting检测其在单环刺螠成体不同组织中的表达水平,结果显示其在体壁中的蛋白表达水平最高,中肠次之,后肠和肛门囊表达量较低,体腔液最低。由于sqr在硫化物暴露后的后肠中表达量最高,进一步对单环刺螠暴露在150μmol/L硫化物环境时后肠中UuGATA B2的表达进行了检测,发现其显著的响应硫化物胁迫,并在暴露12 h时含量达到最高,是对照组的2.32倍,表明UuGATA B2参与了单环刺螠硫化物应激过程。本文首次报道了GATA B2在硫化物应激中的表达特征,为后续深入探讨GATA家族在硫化物应激中的作用提供了基础数据。  相似文献   

15.
Video analysis of a whale-fall discovered in the northeast Pacific Ocean, off Vancouver Island at a depth of 1288 m during ROV diving operations has identified 26 taxa of deep-sea benthic organisms inhabiting the seafloor immediately surrounding remnants of the whale skeleton. A photo-mosaic derived from high-definition video provides a quantitative visual record of the present condition of the site, the species richness, and substrate preference. Only the skull and caudal vertebrae remains of this large whale skeleton are estimated to have been approximately 16.5 m in length. Most organisms identified near the whale-fall are common benthic deep-sea fauna, typical of this water depth and seafloor composition. Much of this species richness comes from sessile suspension feeding cnidarians attached to the numerous glacial dropstones found throughout the area rather than the presence of the whale skeleton. Seep and bone specialists are rare (4 taxa) and may be, in part, a remnant population from a sulphophilic stage of whale-fall decomposition. Evidence of past colonization by Osedax sp. is visible on the remaining bones and we conclude that rapid degradation of the missing bones has occurred at this site as has been observed at whale-falls off central California in Monterey Canyon.  相似文献   

16.
西南印度洋深海热液区铠甲虾初探   总被引:1,自引:0,他引:1  
简述了深海热液区铠甲虾的分类研究现状,整理出铠甲虾总科下属科的形态分类检索表,并对2008年10月-2009年2月中国大洋科考第20航次在西南印度洋深海热液区获得的铠甲虾样品进行详细的形态描述和分类,初步鉴定为5种,隶属于2科5属,分别是:劣柱虾科(Chirostylidae)的折尾虾(Uroptychus sp.),...  相似文献   

17.
Biogenic structures in the deep sea often act as hard substratum 'islands’ for the attachment of encrusting fauna. At an abyssal station in the NE Pacific, stalks of hexactinellid sponges in the genus Hyalonema are habitat islands for species-rich epifaunal communities. An experimental study was conducted to (1) determine the colonization rates of artificial Hyalonema stalks, (2) compare the species composition and diversity of recruits to newly available substrata to that of the natural communities, and (3) examine the vertical distribution of recruits. Four sets of six artificial sponge stalks, constructed of Hyalonema spicules, were deployed at 4100 m depth for 3- to 5-month periods. There was no difference in net colonization or immigration rate among the four deployments. Colonization rates were similar to those reported for other deep-sea, hard substratum recruitment experiments. The taxa that recruited to the artificial stalks were a subset of the taxa found in natural communities. However, several taxa important in structuring natural communities did not recruit to the artificial stalks. The two taxa with the highest invasion rates, a calcareous foraminiferan (Cibicides lobatulus) and a serpulid polychaete (Bathyvermilia sp.), also were the two taxa with greatest relative abundance in natural communities. Vertical distributions of Cibicides and an agglutinated foraminiferan (Telammina sp.) were skewed towards the top of the artificial stalks, potentially because of active habitat selection. These results have several implications for natural Hyalonema stalk communities. Most importantly, species composition and abundance of individuals in the stalk communities appear to be maintained by frequent recruitment of a few common taxa and infrequent recruitment of many rare taxa. An argument is presented for temporal-mosaic maintenance of diversity in these deep-sea, hard substratum communities.  相似文献   

18.
本文利用18S r RNA基因对4株经形态学初步鉴定的梅尼小环藻(Cyclotella meneghiniana)进行了分子鉴定。结果显示,这4株分离自淡水环境(2株)和海水环境(2株)的梅尼小环藻的18S r RNA基因序列基本一致,并与已经报道的梅尼小环藻(登录号为GQ148712和AY496212)聚为一支,不同方法所构建的系统树的支持率分别为99%(邻接法)和98%(最大似然法),表明这4株来自不同环境的藻为同一物种——梅尼小环藻。随后作者利用扫描电镜技术在亚显微水平上对这4株梅尼小环藻进行了观察,结果显示:梅尼小环藻淡水株和海水株具有相当不同的亚显微结构特征。生活在海水的梅尼小环藻藻株具有更大的细胞以及更多的中央支持突。此外,本文还对造成梅尼小环藻种内高水平形态差异的原因以及18S r RNA基因序列是否可以作为小环藻属物种鉴定的分子标记做了分析和讨论。  相似文献   

19.
南海深海鱼类的初步报告   总被引:1,自引:0,他引:1  
南海在我国濒临的四个海中面积最大,而其大陆架宽度则较狭窄,水深在200米以上的深海水域相当广阔。我国过去关于南海深海鱼类的研究报道极少,1962年《南海鱼类志》中曾记载过少数深海鱼类,但具有确切深度记录的仅有8种。在国外文献中,Gilbert和Hubbs(1920), Schultz(1938), Abe(1974 , 1975, 1976 )等曾报道过数种。 本文材料是1959-1960年在海南岛以东海域,水深200-1100米进行底栖生物拖网时所获得的标本。鉴定结果,共71种,分隶于37科,12目,其中34种为我国新记录,7种是我国在南海首次记录。 文内凡是我国新记录的种均有形态描述,并附有外形图,有些种作了分类上的讨论;对我国有过记录的种,只记有地理分布和标本采集记录。此外,就现有资料并参考有关深海鱼类文献,对这些种类的地理分布和深度分布也作了初步分析。由于调查范围较小,拖网次数不多,本文仅为南海鱼类区系提供了一些初步资料。丰富的南海深海鱼类区系,随着我国海洋调查事业的发展,还有待进一步深入研究。  相似文献   

20.
东太平洋海隆深海热液区沉积物古菌多样性分析   总被引:1,自引:0,他引:1  
采用PCR-RFLP方法对东太平洋海隆深海热液区3个站位沉积物中的古菌多样性进行了初步研究.结果显示,从古菌16S rRNA基因文库中随机挑取的296个阳性克隆分属奇古菌门(Thaumarchaeota,47.64%)、广古菌门(Euryarchaeota,44.93%)、泉古菌门(Crenarchaeota,6.77%)和未分类古菌(0.68%),其中优势菌群为奇古菌门的亚硝化侏儒菌属(Nitrosopumilus,35.47%)和广古菌门的热原体纲(Thermoplasmata,27.03%),DHVE3、DHVE5、DHVE6、MBGB和MBGE类群在沉积物样品中也均有发现.另外,3个站位沉积物中古菌类群组成存在差异,S5-TVG1站位样品文库的97个古菌克隆分属奇古菌门(49.48%)、广古菌门(49.48%)和泉古菌门(1.03%),S14-TVG10站位样品文库的103个古菌克隆由奇古菌门(84.47%)和广古菌门(15.53%)组成,S16-TVG12站位样品文库的96个古菌克隆包括广古菌门(71.88%)、泉古菌门(19.79%)、奇古菌门(6.25%)和未分类古菌(2.08%).研究结果表明,东太平洋海隆深海热液区沉积物中古菌多样性丰富,存在着许多新的古菌菌群;不同站位古菌菌群结构以及多样性存在差异,这与其所处环境的热液活动密切相关.  相似文献   

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