山瑞鳖生物学研究

山瑞鳖（Ｐａｌｅａｓｔｅｉｎｄａｃｈｎｅｒｉ）为国家Ⅱ级保护动物,主要分布于华南地区。作者于１９９６年１０月～１９９７年１０月对人工养殖条件下的山瑞鳖生物学习性进行了研究。１材料和方法１１动物来源山瑞鳖购自海南屯昌县。共４３２只,鳖龄４～６岁,体重...     

山瑞鳖Trionyx steidachneri染色体组型

本文以骨髓为材料,用秋水仙—低渗—空气干燥制片法,制备染色体标本,对山瑞鳖的染色体组型进行研究。其2n=66 NF=60,其中近中着丝粒染色体4对,近端着丝粒染色体4对和端部着丝粒14对。并有11对点状染色体。山瑞鳖与鳖的染色体数目是十分相近的。     

山瑞鳖驯化养殖、保护及其开发利用的初步研究Ⅱ.山瑞鳖的生长、饲养管理及保护利用

(续上期 )4　山瑞鳖的稚幼鳖的生长4 1　刚孵出的山瑞稚鳖的大小　测量了不同窝次刚孵出 3 5只稚鳖 (在鳖类从卵内刚孵出的鳖通称稚鳖 ,至于稚鳖期与幼鳖的界限则无定论。本文对山瑞鳖按体重划分为 :5 0 ｇ以下为稚鳖期 ,5 0～ 40 0ｇ为幼鳖期 ,40 0～ 40 0 0 ｇ为商品鳖 ,40 0 0 ｇ以上视为成年鳖 ) ,平均体重 7 4(6 0～ 9 1 ) ｇ ,背甲长宽 3 7 6× 3 0 9(3 0× 2 3～ 47× 3 4)ｍｍ ,腹盘长 2 5 0 (2 4～ 2 7)ｍｍ。4 2　山瑞幼鳖的生长　前述刚孵出的 3 5只稚鳖经过7个月的加温 (2 5℃ )饲养结果 ,除中途死亡 1 1只外 ,剩下 2 4只幼鳖…     

基于线粒体Cytb基因全序列探讨两爪鳖和山瑞鳖的系统进化关系

采用PCR方法对两爪鳖(Carettochelys insculpta)和山瑞鳖(Pdea steindachneri)mtDNA的细胞色素b基因(Cytb)进行了扩增和测序,并结合GenBank中已公布的其它15种龟鳖类和两种鳄类的同源序列,进行了序列变异比较和系统发生分析.以凯门鳄和扬子鳄为外群,采用邻接(neighbor ioining,NJ)法、最大简约(maximum likelihood,ML)法和最大似然(maximum parsimony,MP)法重建分子系统树.结果均支持将龟鳖目分为3支:侧颈龟科(Pelomedusidae)(非洲侧颈龟Pelomedusa subrufa),两爪鳖科(Carettochelyidae)(两爪鳖Carettochelys insculpta)和一支由其它15种现生龟鳘类组成的进化支.在这里两爪鳘科被认为可能代表一新的亚目;而山瑞鳖聚于鳖科(Trionychidae)中,与中华鳌(Pelodiscus sinensis)最先聚成一支,再依次与马来鳖(Dogania subplana)、非洲鳖(Trionyx triunguis)、印度箱鳖(Lissemys punctata)聚成一组.     

三种鳖线粒体DNA细胞色素b基因序列的比较分析

对中华鳖、砂鳖和山瑞鳖线粒体DNA细胞色素b基因进行了引物设计、PCR扩增、序列测定和PCR-PFLP(Polymerase chain reaction-restriction fragment length polymorphism)分析。研究结果表明中华鳖、砂鳖与山瑞鳖线粒体DNACytb基因的序列全长相同,均为1140bp,其A、C、G、T含量相似,分别为378个(33.2%)、322个(28.2%)1、22个(10.7%)、318个(27.9%)、373个(32.7%)、324个(28.4%)、124个(10.9%)、319个(28.0%)、380个(33.3%)3、30个(28.9%)、127个(11.1%)、303个(26.7%)。同源性及序列差异率分析表明:中华鳖与砂鳖b基因序列的同源性为92.3%,中华鳖、山瑞鳖的为85.0%,砂鳖、山瑞鳖的为84.1%;中华鳖与砂鳖b基因核苷酸序列间的差异率为7.7%,中华鳖、山瑞鳖间的序列差异率为15.0%,砂鳖、山瑞鳖间的序列差异率为15.9%,而中华鳖、砂鳖、山瑞鳖各自个体间的序列差异率分别为2.37%、0.88%和0.18%,种间差异显著。用内切酶酶切分析其扩增产物,结果表明:用内切酶NdeⅠ可准确鉴别砂鳖,而用内切酶BamHⅠ则可准确鉴别山瑞鳖。内切酶NdeⅠ和BamHⅠ的联用分析,可使这三种鳖在分子水平都得到明确的鉴定。从三种鳖线粒体DNACytb基因核苷酸序列的显著差异和酶切位点的变化,可以进一步证明砂鳖是不同于中华鳖的鳖属一新种。     

中国鳖土蝽属记述

记述中国鳖土蝽属Adrisa 3种,即大鳖土蝽Adrisa magna,黑鳖土蝽Adrisa birmana和台湾鳖土蝽Adrisa rawlinsi.其中黑鳖土蝽Adrisa birmana为中国首次记录种,Adrisa nigra在我国的分布实际应属于Adrisa birmana.编制了鳖土蝽属中国已知种分种检索表,提供了新记录种的特征图.研究标本保存于南开大学昆虫学研究所.     

中国鳖属的分类历史简述

鳖属Pelodiscus隶属于鳖科Trionychidae,是我国分布较多的龟鳖类动物.现生龟鳖类物种繁多,中国已报道了鳖属动物4种,分别是中华鳖Pelodiscus sinensis、东北鳖Pelodiscus maackii、砂鳖Pelodiscus axenaria和小鳖Pelodiscus parviformi...     

中国鳖科Pelodiscus属一新种研究

本邀请季１个产自桂东北及邻近地区的鳖类新种－小鳖。该鳖种生活在水质清洁,砂砾石底质的江段,６０年代以前出产额丰,现已难觅踪影。对野生小鳖资源的保护已迫在眉睫。     

中华鳖多态性微卫星标记跨物种扩增研究

微卫星是一种优秀的分子标记,并广泛应用于生物和医学的各个领域。但微卫星标记的开发成本较高,因而,利用近缘种已开发的微卫星标记已成趋势。利用本实验室已开发的21个中华鳖微卫星对鼋、斑鳖、山瑞鳖、刺鳖、佛罗里达鳖、两爪鳖、黄喉拟水龟和乌龟等8个物种进行跨物种检验。结果表明,4个微卫星位点(CST21、CST42、CST50和CST52)的引物能在所有8只个体中稳定扩增;而CST16在所有个体中都不能扩增出目的片段。跨物种扩增山瑞鳖结果最好,21个位点中有20个位点能稳定扩增;而乌龟扩增效果最差,只有6个位点能被扩增出目的产物。总之,中华鳖的21个微卫星位点多数可以在鳖科内各属间进行跨物种扩增,部分可以在跨科物种间扩增。     

仿生养殖鳖与温室养殖鳖形态特征的比较

对体重为531－615g仿生养殖鳖与体重575－613g的温室养殖鳖进行形态观测,结果表明,在等背甲长、宽时,仿生养殖鳖的体高显著较温室养殖鳖为小,裙边宽显著较温室养殖鳖为大,呈更扁平的体型;仿生养殖鳖的爪型较尖,温室养鳖的爪尖圆钝;在等体重的鳖中,温室养殖鳖组织中的成形脂肪块重和肝脏重均显著高于仿生养殖鳖（P＜0．01）,表明温室养殖鳖可食部分中脂肪含量增加,同时发现温室养殖鳖往往有脂肪肝异变现象。     

水稻内颖畸形或缺失基因OsAPP1的图位克隆及表达分析

在育种基地材料中发现一株内颖畸形或缺失(abnormal or absent palea)突变体,将其命名为app1。该突变体在营养生长时期发育正常,但抽穗后突变体表现出内颖畸形(比外稃短导致颖壳不闭合,或者出现两个内稃)或缺失,其花粉育性为55.52%,结实率为6.48%,千粒重为10.811 g,种子发芽率为55.21%。以突变体app1与日本晴杂交构建了F1和F2群体,F1颖壳表型正常,F2群体出现内颖畸形和正常表型分离,内颖正常和突变表型分离比例为3∶1,表明app1内颖突变表型由单隐性核基因控制。以F2为分离群体,将app1精细定位于第3染色体上,位于分子标记ID4231和ID4246之间,遗传距离1.3 cM,对应物理距离为13.2 kb。该区段内完全包含1个开放阅读框,包含两个部分开放阅读框,经过测序分析发现候选基因LOC_Os03g11614启动子区发生点突变和245 bp缺失,qRT-PCR分析证实LOC_Os03g11614为OsAPP1基因。已有报道LOC_Os03g11614编码OsMADS1,是调控水稻花器官发育的重要明星基因,其不同位置的突变可以导致叶状颖壳和不育、以及控制籽粒大小。与3000份水稻种子资源SNP/Indel变异类型对比分析发现,突变体app1启动子的突变完全不同于现已OsMADS1研究报道突变类型,且与数据库中的自然突变类型多数不同。因此,本研究发现的app1突变体,是以往报道中从未出现的OsMADS1启动子发生突变的新型突变,且该类突变导致了其降低表达量,并产生了不同于前人研究的新表型,这为深入研究OsMADS1基因在水稻花器官发育中的功能提供了新的种质资源和思路。     

BEAK LIKE SPIKELET1 is Required for Lateral Development of Lemma and Palea in Rice

Lemma and palea are unique floral structures found only in Poaceae, and are responsible for protecting the inner floral organs and kernels from environmental stresses. However, the mechanism underlying specification of their morphology remains unclear. In this study, we characterized a rice mutant, beak like spikelet1 (bls1), which specifically affects development of the lemma and palea. In bls1 mutant, floral-organ identity and floral-organ patterning are normal, and the defects occur at the stage of the lemma and palea expansion, whereas the other aspects of floral architecture and form are not affected. We isolated BLS1 by positional cloning and found that it encodes a protein with a conserved domain of unknown function. BLS1 is expressed strongly in young inflorescence, specifically the young lemmas and paleas of spikelets. Subcellular localization analysis showed that BLS1 is localized in the nucleus. Expression of the AP1-like and SEP-like floral homeotic genes were not changed in the bls1 mutant. Our study suggested that BLS1 is required for lateral development of the lemma and palea and does not function at stages of floral-organ initiation and patterning.     

Light and electron microscopic studies of the skin of the Palembang puffer,Tetraodon steindachneri (Teleostei,Tetraodontidae)

Summary The skin ofTetraodon steindachneri is morphologically and cytologically adapted to the habits and locomotion of the fish, as well as to its ability to expand its body into a nearly spherical shape. Negative buoyancy, which facilitates precise maneuvers near the bottom, is achieved primarily by a very thick dermis. Various special features of the skin enable it to withstand the mechanical stresses of extreme expansion and deep folding: (1) the absence of a covering such as a cuticle on the outer surface of the epidermis, (2) the lack of scales, (3) the pronounced interdigitation of the epidermal cells, (4) the cytoskeleton of the filament-containing cells, and (5) the stratum compactum of the dermis. The spines, which inT. steindachneri can be extended and retracted, are derived, like the spines of diodontidae, from the scales of other teleosts. Each spine comprises cellular and acellular components, which together produce a complicated bilaterally symmetrical structure. Movement of the spines is mainly a passive mechanical concomitant of distension of the body, though active processes cannot be ruled out. The biological significance of the spine apparatus ofT. steindachneri is discussed.Abbreviations af annular fold - amc apical mucous cell - bv blood vessel - bm basal membrane - cf collagen fibers - cfb collagen fiber band - cv central vacuole - d desmosome - de dermis - ed epidermis - f tonofilaments - fcc filament-containing cell - gc granular cell - id interdigitation - md modified dermis - mr microridges - n nucleus - nf nerve fibers - s spine - sc stratum compactum - sk skeleton of spine - sl stratum laxum - smc sacciform mucous cell - sub subcutis - vc vacuole cell     

Two new species of Duplicibothrium Williams & Campbell, 1978 (Tetraphyllidea: Serendipidae) from the Pacific cownose ray Rhinoptera steindachneri

Two new tetraphyllidean species, Duplicibothrium cairae n. sp. and D. paulum n. sp., are described from Pacific cownose rays Rhinoptera steindachneri collected from the Gulf of California. D. cairae n. sp. differs from the only other known species in this genus, D. minutum, in its possession of two posteriorly bifurcating longitudinal septa on each bothridium and having a greater number of loculi per bothridium, wider bothridia and a greater number of segments per worm. D. paulum n. sp. differs from the above two species in being shorter, having two continuous longitudinal septa on each bothridium, rather than posteriorly bifurcating or absent longitudinal septa, having a greater number of loculi per bothridium and having fewer segments per worm. The generic diagnosis of Duplicibothrium is amended to reflect the inclusion of the two new species. Species of Duplicibothriumappear to be restricted to host species of the genus Rhinoptera. Systematic information gained from the study of these two new species supports the monophyly of the tetraphyllidean family Serendipidae and suggests that Duplicibothrium shares a phylogenetic heritage with species in the genera Glyphobothrium and Serendip, taxa that are also parasitic in cownose rays. Evidence for a phylogenetic relationship between serendipid species and species of Dioecotaenia is discussed, as are potential molluscan hosts for cestode species in Duplicibothrium and Dioecotaenia.     

The fine structure of the fin musculature in two teleost species with different swimming modes,the puffer,Tetraodon steindachneri,and the goldfish,Carassius auratus

Summary Puffer fish (Tetraodon steindachneri) can execute precise maneuvers due to their highly specialized mode of propulsion. In the conventional locomotion exemplified by the goldfish (Carassius auratus), the fish thrusts are generated by lateral beating of the caudal fin. In contrast, the puffer generates its propulsive force by very rapid undulating movements of the pectoral, dorsal and anal fins. The fine structure of the fin muscles is identical in the two species of fishes, despite the differences in fin movement; cytologically, the fibers are intermediate between those of red and of white muscle. On the other hand, both the fusion frequency and the number of motor endplates are considerably higher in the fin muscles of the puffer than in those of the goldfish.     

壳聚糖酶的克隆表达与壳寡糖的制备分析

目的:克隆壳聚糖酶基因于大肠杆菌中实现高表达,制备壳寡糖。方法:以枯草芽孢杆菌总DNA为模板扩增壳聚糖酶基因(CSN),克隆至载体pET23a(+)上,转化菌株BL21(DE3)。重组子经0.5 mmol/L IPTG诱导后,SDS-PAGE和质谱检测与鉴定重组酶。酶纯化后水解壳聚糖,薄层色谱分析其水解产物。结果:质谱证明壳聚糖酶(31.5kDa)成功表达,表达量占菌体总蛋白的45%左右。纯化后重组酶浓度为900 mg/L,纯度95%、回收率85%,酶活力为10 000 U/mg。壳聚糖降解产物为壳二糖至壳四糖。结论:原核表达载体pET23a(+)-CSN构建正确,壳聚糖酶表达量与活性高,适用于水解壳聚糖制备壳寡糖。