Isolation of additional polymorphic tri‐ and tetranucleotide microsatellite loci for the giant Australian cuttlefish (Sepia apama)

We isolated 10 polymorphic microsatellite loci for the giant Australian cuttlefish, Sepia apama, from a genomic library enriched for (AAC)_n and (AAAG)_n repetitive elements. In the nine loci that reliably amplified, the number of alleles ranged from four to 12 per locus with observed heterozygosity ranging from 0.343 to 0.926. These and a previously developed set of six loci will be useful for analysis of genetic structure of populations and determining input to a massive seasonal breeding aggregation in northern Spencer Gulf, Australia.     

三种乌贼内骨骼生化成分研究

曼氏无针乌贼（Sepiella maindroni）和金乌贼（Sepia esculenta）的内骨骼称为海螵蛸,可用于制酸、止血等。通过对曼氏无针乌贼、金乌贼和虎斑乌贼（Sepia pharaonis）内骨骼生化成分的比较,有望实现传统中药海螵蛸原料质量的提升和替代。分别使用烘干干燥法、高温灼烧法、凯氏定氮法、索氏提取法、酸碱浸泡法、茚三酮柱后衍生离子交换色谱法、离子发光色谱法检测水分、灰分、粗蛋白、粗脂肪、粗甲壳素、氨基酸及矿物质。结果显示：三种内骨骼营养成分中,虎斑乌贼水分和粗蛋白含量最高,分别为（2.52±0.16）%和（3.43±0.10）%;金乌贼灰分和粗脂肪含量最高,分别为（94.7±0.26）%和（0.24±0.04）%;甲壳素含量最高的为曼氏无针乌贼内骨骼,为（9.48±0.36）%,约为其他两种的1.50倍。三种乌贼内骨骼共检出15种氨基酸,其中必需氨基酸（EAA）7种,半必需氨基酸（HEAA）1种,非必需氨基酸（NEAA）7种,三种乌贼骨的EAA/TAA为44.64%~47.09%,符合FAO/WHO中对于蛋白质EAA/TAA的理想评定标准。金乌贼内骨骼的钙含量最高（3.93×10⁵ mg/kg）、曼氏无针乌贼的钠含量最高（1.02×10⁴ mg/kg）、虎斑乌贼的钾含量最高（589.5 mg/kg）。可见三种乌贼内骨骼均是低脂肪、高甲壳素、高矿物质的中药。虎斑乌贼内骨骼蛋白和灰分营养成分含量较为丰富,是否可以作为传统海螵蛸的替代品,值得进一步探讨。     

A fish‐eye view of cuttlefish camouflage using in situ spectrometry

Cuttlefish are colour blind yet they appear to produce colour‐coordinated patterns for camouflage. Under natural in situ lighting conditions in southern Australia, we took point‐by‐point spectrometry measurements of camouflaged cuttlefish, Sepia apama, and various natural objects in the immediate visual surrounds to quantify the degree of chromatic resemblance between cuttlefish and backgrounds to potential fish predators. Luminance contrast was also calculated to determine the effectiveness of cuttlefish camouflage to this information channel both for animals with or without colour vision. Uniform body patterns on a homogeneous background of algae showed close resemblance in colour and luminance; a Uniform pattern on a partially heterogeneous background showed mixed levels of resemblance to certain background features. A Mottle pattern with some disruptive components on a heterogeneous background showed general background resemblance to some benthic objects nearest the cuttlefish. A noteworthy observation for a Disruptive body pattern on a heterogeneous background was the wide range in spectral contrasts compared to Uniform and Mottle patterns. This suggests a shift in camouflage tactic from background resemblance (which hinders detection by the predator) to more specific object resemblance and disruptive camouflage (which retards recognition). © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 535–551.     

Distribution of oxytocin-like and vasopressin-like immunoreactivities within the central nervous system of the cuttlefish, <Emphasis Type="Italic">Sepia officinalis</Emphasis>

We have investigated the distribution of oxytocin/vasopressin (OT/VP) superfamily peptides in the central nervous system (CNS) of the cuttlefish, Sepia officinalis, by using antibodies raised against mammalian OT and VP. Several populations of OT-like and VP-like immunoreactive cell bodies and fibers were widely distributed in cerebral structures involved in learning processes (vertical lobe complex, optic lobes), behavioral communication (peduncle, lateral basal and chromatophore lobes), feeding behavior (inferior frontal, brachial and buccal lobes), sexual activity (dorsal basal, subpedunculate, olfactory lobes), and metabolism (visceral lobes). The two most remarkable findings of this study were the occurrence of OT-like immunoreactivity in many amacrine cells of the vertical lobe and the dense accumulation of VP-like immunoreactive cell bodies in the subpedunculate 1 lobe. No double-immunolabeled cell bodies or fibers were found in any lobes of the CNS, indicating, for the first time in a decapod cephalopod mollusc, the existence of distinct oxytocinergic-like and vasopressinergic-like systems. The widespread distribution of the immunoreactive neurons suggests that these OT-like and VP-like peptides act as neurotransmitters or neuromodulators. This research was supported by grants from the “Région Basse-Normandie” (FRANCE) and the LARC-Neurosciences network (FRANCE).     

Cuttlefish use visual cues to control three-dimensional skin papillae for camouflage

Cephalopods (octopus, squid and cuttlefish) are known for their camouflage. Cuttlefish Sepia officinalis use chromatophores and light reflectors for color change, and papillae to change three-dimensional physical skin texture. Papillae vary in size, shape and coloration; nine distinct sets of papillae are described here. The objective was to determine whether cuttlefish use visual or tactile cues to control papillae expression. Cuttlefish were placed on natural substrates to evoke the three major camouflage body patterns: Uniform/Stipple, Mottle and Disruptive. Three versions of each substrate were presented: the actual substrate, the actual substrate covered with glass (removes tactile information) and a laminated photograph of the substrate (removes tactile and three-dimensional information because depth-of-field information is unavailable). No differences in Small dorsal papillae or Major lateral mantle papillae expression were observed among the three versions of each substrate. Thus, visual (not tactile) cues drive the expression of papillae in S. officinalis. Two sets of papillae (Major lateral mantle papillae and Major lateral eye papillae) showed irregular responses; their control requires future investigation. Finally, more Small dorsal papillae were shown in Uniform/Stipple and Mottle patterns than in Disruptive patterns, which may provide clues regarding the visual mechanisms of background matching versus disruptive coloration.     

Vergleichende elektronenmikroskopische Untersuchungen an den zentralen Herzorganen von Cephalopoden (Sepia officinalis)

Zusammenfassung Die vergleichenden licht- und elektronenmikroskopischen Untersuchungen am Kiemenherzen von Sepia officinalis und Loligo vulgaris verschiedener Altersstufen zeigen eine Doppelfunktion dieses Organs als Herz- und Drüsenorgan auf. — Die quantitativ wenig hervortretende quer- resp. schräggestreifte Muskulatur ist nicht geschichtet und bildet ein lockeres Maschenwerk, in dem in großer Zahl ovoide Zellformen mit größeren Einschlußkörpern eingelagert sind. — Mit dem Auftreten von A-, I- und Z-Banden und der Ausbildung eines SR- und T-Systems entspricht die Organisation der Muskelfasern der des Zentralherzens (Schipp und Schäfer, 1969 b). Im Gegensatz zum Zentralherzen wird jedoch in der Kiemenherzmuskulatur nur ein Endigungstyp der wahrscheinlich monoaminergen Nervenfasern nachgewiesen.Die Zellformen zwischen den Muskelzellen treten in 2 Typen auf, die wahrscheinlich als Ausdruckverschiedener Funktionszustände zu werten sind. Ihre Organisation (Gehalt an Einschlußkörpern, Ergastoplasma und Dictyosomen sowie Exocytosevorgänge) deutet auf eine innersekretorische Funktion hin. Die intrazellulären Vorstufen des Sekretes besitzen ein ähnlich ausgebildetes kristallines Grundmuster wie das extrazelluläre Hämocyanin. Es ist daher nicht auszuschließen, daß diesen Zellen eine blutbildende Funktion zukommt.

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Comparative electron microscopic studies of the central cardiac organs of cephalopods (Sepia officinalis)Ultrastructure and function of the branchial heart

Summary Comparative light and electron microscopic studies of the branchial heart of Sepia officinalis and Loligo vulgaris at different ages showed that the organ functions both as a heart and a glandular structure. A small number of cross- or obliquely-striated muscle cells form a loose network that contains numerous ovoid cells with large inclusion bodies. The organization of A-, I-, and Z-bands, and the formation of SR- and T-systems in the branchial heart muscle resembles those in the central heart muscle (Schipp and Schäfer, 1969 b). On the other hand, only one type of monoaminergic axon terminals is observed in the branchial heart.The cells among the branchial heart muscle fibers are of two types, that may be a representation of different functional states. The organization of the cells (in reference to cell inclusions, ergastoplasm, dictyosomes) suggests endocrine function. The cell inclusions have a crystalline inner pattern like that of extracellular hemocyanin, suggesting that the ovoid cells may have a hemopoietic function.

Unterstützung durch die Deutsche Forschungsgemeinschaft.     

拟目乌贼卵子发生与卵巢发育

为了丰富拟目乌贼(Sepia lycidas)生物学资料, 为人工育苗与养殖提供理论依据, 采用解剖学和组织学的方法, 对水泥池养殖条件下拟目乌贼卵子发生和卵巢发育进行了研究。结果表明: 经过6个月水泥池养殖, 平均体重为256.34 g, 最大体重达到457.08 g, 个别发育成熟, 绝大部分未达性成熟。卵子发生不同步, 根据细胞形态、细胞大小、滤泡细胞形态和卵黄形成情况可分为卵原细胞阶段(卵原细胞期)、原生质生长阶段(无滤泡期、单层滤泡期和双层滤泡期)、间质生长阶段(滤泡内折早期、滤泡内折中期和滤泡内折晚期)和营养质生长阶段(卵黄发生早期、卵黄发生晚期和成熟期), 共4个阶段10个时期。卵巢发育根据外观形态、性腺指数变化和切面上各期细胞所占的比例, 可分为形成前期、形成期、小生长期、大生长期、成熟前期和成熟期6个时期。拟目乌贼繁殖周期为一年。       

Location of intrinsic and inducible phenoloxidase activity in molluscan hemocyanin

The phenoloxidase (PO) activity of the hemocyanins (Hcs) from two molluscan species, the gastropod Helix pomatia (Hp) and the cephalopod Sepia officinalis (So), was studied. With catechol as substrate the Hcs showed a weak o-diPO activity, which was moderately enhanced on limited proteolysis with subtilisin. The sites in the Hc molecules mainly responsible for this activity were identified. The highest intrinsic o-diPO activity and also by far the highest level of induction were found in the functional units (FUs) Hp f and So g, isolated from Hp beta-Hc and So Hc (subunit 2), respectively. The results thus support the earlier conclusion, made on the basis of sequence homology between molluscan Hcs, that Hp f and So g are functional and structural analogues. The subtilisin treatment of Hp f also induced monoPO activity, considered to be at the origin of browning of the sample.     

Central distribution and three-dimensional arrangement of fin chromatophore motoneurons in the cuttlefish Sepia officinalis

Cephalopod body patterning is a most complex invertebrate behavior. Generated primarily by pigment-containing chromatophore organs, this behavior enables rapid alteration of body coloration as a result of direct innervation of chromatophores by motoneurons. This study focuses on location and arrangement of fin chromatophore motoneurons in the cuttlefish Sepia and investigates the possibility of central topography. Retrograde labeling of topographically arranged fin nerve branches in the periphery revealed the posterior subesophageal mass (PSEM) of the brain as the primary location of fin chromatophore motoneurons; within this region, most cells were located in the posterior chromatophore and fin lobes. Additionally, a small percentage of labeled motoneurons occurred in the anterior subesophageal mass and the stellate ganglia. Data from three-dimensional reconstructions of PSEMs showed the arrangement of labeled motoneurons within individual lobes; these data suggest no obvious topographic arrangement. Further, electrical stimulation of the PSEM generated chromatophore activity on the fin and mantle. These stimulation results, coupled with the retrograde labeling, suggest that chromatophore motoneurons are located across multiple PSEM lobes.