VASCULAR PATTERNS IN STEMS OF ARACEAE: SUBFAMILIES COLOCASIOIDEAE,AROIDEAE AND PISTIOIDEAE

The stem vasculature of ten genera of Colocasioideae and three genera of Aroideae was analyzed by films of series of cross sections. The technique was unsuited for the numerous tuberous genera of Aroideae (and Pistia), which have shortened internodes. The Colocasioideae has long been recognized as one of the most natural large assemblages in the Araceae, a concept further supported by information from stem anatomy and vasculature. All species examined have amphivasal axial bundles that undergo frequent anastomosis and bifurcation of a seemingly irregular kind. Syngonium is the only viny genus and is exceptional in a number of anatomical features which are associated with its unusual morphology. One of the principle points of diversity in the Colocasioideae is the presence or absence of a permanent cortical vascular system. All four genera with a permanent cortical system (Caladiopsis, Caladium, Xanthosoma, and Syngonium) are neotropical. In the Aroideae (and Pistioideae) all of the tuberous genera have a highly condensed vascular system. Genera with elongated internodes (Stylochiton, Lagenandra, Cryptocoryne) also have a similar pattern, which makes taxonomic comparisons based on stem vasculature in the Aroideae of little value. Branch trace insertion is much less well developed in Colocasioideae and Aroideae than in most other subfamilies.     

Molecular cloning and nucleotide sequence of cDNA for sporamin,the major soluble protein of sweet potato tuberous roots

Summary Sporamin accounts for more than 80% of the total soluble proteins of tuberous roots of sweet potato, but very little, if any, in other tissues of the same plant. In vitro translation of RNA fractions from the tuberous roots in wheat germ extract and subsequent immunoprecipitation with the antibody to sporamin indicated that this protein is synthesized by membrane-bound polysomes as a precursor 4 000 daltons larger than the mature protein. A cDNA expression library was constructed from the total poly(A)⁺ RNA from the tuberous roots by a vector-primer method, and an essentially full-length cDNA clone for the sporamin mRNA was selected by direct immunological screening of the colonies. Northern blot analysis showed that sporamin mRNA is approximately 950 nucleotides in length and is specifically present in tuberous roots and very little, if any, in leaves, petioles and non-tuberous roots. Nucleotide sequence of the cDNA predicts a 37 amino acid extension in the precursor at the amino-terminus of the mature protein.     

PAURODENDRON,A RHIZOMORPHIC LYCOPOD

From middle Pennsylvanian coal balls collected in Kansas and Illinois the ligules and rhizomorph of Paurodendron have been illustrated. Assignment of Paurodendron to the Lycopsida is corroborated. Discovery of the root-bearing portion of this Carboniferous lycopod establishes a diminutive, phyletic line in the Paleozoic with rhizomorphs smaller than many species of Isoeles. Paurodendron resembles the selaginelloid line more closely than other rhizomorphic types. Anatomical comparisons of Paurodendron with roots and root-bearing structures of lycopods are made; the root-bearing and a representative leaf-bearing portion of Paurodendron fraiponti have been reconstructed. The specific diagnosis has been emended, and the three species described by Fry have been reduced to one.     

STRUCTURE AND DEVELOPMENT OF THE FLOWER AND FRUIT OF PERESKIA DIAZ-ROMEROANA

Pereskia diaz-romeroana and its putative relatives are scandent plants with vigorously growing long shoots, small flowers and fruits, and tuberous root systems. Except for size, floral development parallels that in other pereskias. The gynoecium has three to six carpels, is basically superior with axlie placentation, and is partially divided into locules by the connate carpel margins. The closest relative of these Andean forms appears to be P. aculeata.     

Ear morphology of the frog-eating bat (Trachops cirrhosus,family: Phyllostomidae): Apparent specializations for low-freqency hearing

The frog-eating bat (Trachops cirrhosus) is unusual among bats studied because of its reliance on low-frequency (<5 kHz) sounds emitted by frogs for prey localization. We investigated the ear of this bat in order to identify anatomical features that might serve as adaptations for low-frequency hearing. Trachops cirrhosus has a variety of anatomical features that might enhance low-frequency hearing, either by increasing sensitivity to low-frequency sounds or expanding the total frequency range to include lower frequencies. These bats have long pinnae, and a long and wide basilar membrane. The basal portion of the basilar membrane is much stiffer than the apical portion, and the basal portion of the tectorial membrane is more massive than the apical portion. There is also a concentration of mass in the apical portion of the cochlea. T. cirrhosus possesses the largest number of cochlear neurons reported for any mammal, the second highest density of cochlear neurons innervation known among mammals, and three peaks of cochlear neuron density. Other bats have two peaks of cochlear neuron density, lacking the apical concentration, while other mammals usually have only one. T. cirrhosus differs from most other small mammals and bats in characteristics of the apical portion of the cochlea, i.e., that area where the place theory of hearing predicts that low frequencies are detected.     

Immunohistochemical identification of substance P in cutaneous sensory organs (electroreceptors) of gymnotid teleost fish

Summary The distribution of the neuropeptide substance P, which is considered to be a neurotransmitter or neuromodulator of the central nervous system, has been studied in the cutaneous electroreceptor organs (tuberous and ampullary organs) of 3 species of gymnotid fish: Apteronotus leptorhynchus, Eigenmannia virescens and Sternopygus sp. Immunohistochemical data have revealed that substance P is never present in the afferent fibers but is specifically localized in the electroreceptors of the three species examined. Substane P immunoreactivity is strictly localized in the sensory cells of the ampullary organs of all three species and in those of the tuberous organs of Apteronotus leptorhynchus and Sternopygus sp. In contrast, weak substance P immunoreactivity was observed only in certain tuberous sensory cells of Eigenmannia. Substance P immunoreactivity was also found in the accessory cells of certain organs: it was detected in the two types of accessory cells of the tuberous organs of Eigemmannia virescens, in the accessory cells type 2 of the tuberous organs of Sternopygus sp., and in all accessory cells of ampullary organs of Sternopygus sp. and Apteronotus leptorhynchus. In Sternopygus sp., positive staining was only evident if the substance P antibody was used at low concentration. Immunoreactivity for substance P in the sensory cells suggests that it has a transmitter or modulator function in these electroreceptors; the presence of substance P in the accessory cells remains to be explained.     

Differential distribution of ampullary and tuberous processing in the torus semicircularis of Eigenmannia

Summary Gymnotiform electric fish sense low-and high frequency electric signals with ampullary and tuberous electroreceptors, respectively. We employed intracellular recording and labeling methods to investigate ampullary and tuberous information processing in laminae 1–5 of the dorsal torus semicircularis of Eigenmannia. Ampullary afferents arborized extensively in laminae 1–3 and, in some cases, lamina 7. Unlike tuberous afferents to the torus, ampullary afferents had numerous varicosities along their finest-diameter branches. Neurons that were primarily ampullary were found in lamina 3. Neurons primarily excited by tuberous stimuli were found in lamina 5 and, more rarely, in lamina 4. Cells that had dendrites in lamina 1–3 and 5 could be recruited by both ampullary and tuberous stimuli. These bimodal cells were found in lamina 4. During courtship, Eigenmannia produces interruptions of its electric organ discharges. These interruptions stimulate ampullary and tuberous receptors. The integration of ampullary and tuberous information may be important in the processing of these communication signals.Abbreviations JAR jamming avoidance response - EOD electric organ discharge - S1 sinusoidal signal mimicking fish's EOD - S2 jamming signal - Df frequency difference (S2-S1) or between a neighbor's EODs and fish's own EODs - CNS central nervous system     

Mycorrhizal differences between genuine roots and tuberous roots of adult plants ofSpiranthes sinensis var.amoena (Orchidaceae)

Genuine roots ofSpiranthes sinensis var.amoena were infected with the mycorrhizal fungusRhizoctonia repens immediately after root formation in autumn. Infection by the mycorrhizal fungus extended, reaching a maximum the following early summer. The amount of living mycorrhizal fungus in the genuine roots dramatically declined in the flowering season, and then the roots decomposed. Tuberous roots were formed in spring. Mycorrhizas were limited to local infections and did not spread along the roots. The infection level of living mycorrhizal fungus in the tuberous roots was less than in the genuine roots throughout the year. The amount of dead fungal coils in the tuberous roots increased as the tuberous roots aged. The mycorrhizal characteritics of tuberous roots ofS. sinensis var.amoena were totally different from those of genuine roots although the tuberous roots morphologically resembled the genuine roots. Contribution No. 96, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.     

The Genus Obelus Hartmann, 1842 (Gastropoda, Pulmonata, Helicoidea) and its Phylogenetic Relationships

The genus Obelus, so far known from shells only, is re-described on the basis of the anatomy of its genital system. Its range is here restricted to north-western Africa and the Canary Islands. Four species are traditionally listed for the Canary Islands: Obelus despreauxii, O. moderatus, O. mirandae and O. cyclodon. The presence of the last species on the Canary Islands is doubtful, whereas the fossil/subfossil presence of O. pumilio is documented. The species Helix morata also belongs to the genus, as well as a new species, O. discogranulatus sp. nov. The genital systems of all confirmed extant Canarian species are shown. Obelus has a peculiar vaginal stimulator appendix (“appendicula”) which is homologous to the penial appendix of the Orthurethra and to the stimulatory organ of other Stylommatophora, with the exception that the A₃ portion is missing. The genus is diagnosed by characters of the vaginal stimulator appendix, such as a curved, finger-like A₂ portion of the appendicula ending proximally in a blind, well-developed muscular sac, and by the slender tubular A₄ portion arising laterally from the muscular sac duct. We conclude that Obelus belongs to the Cochlicella group because it shares an appendicula with the other genera of the group. However, it differs in anatomical details of this structure. The Cochlicella group should be recognized as a separate family Cochlicellidae Schileyko, 1972, with close relationships to the Helicellidae and the Hygromiidae. A new diagnosis for Cochlicellidae is proposed and its phylogenetic relationships are discussed.This is: Notes on the Malacofauna of the Canary Islands, No. 46.     

Development, during ontogenetic development of gymnotids, of substance p expression in tuberous organs (electroreceptors)]

The evolution of the neuropeptidic expression of Substance P has been investigated with immunohistochemistry in the cutaneous electroreceptors, tuberous organs, during ontogenetic development of Apteronotus leptorhynchus. In the present data, antiSP antiserum has been applied to serial sections of Apteronotus leptorhynchus larvae obtained from several egg layings. Larvae were taken during development from hatching up to one hundred days old. SP immunoreactivity appeared just after hatching, in the epidermal zones which give rise to cutaneous sense organs. Four days after hatching, the tuberous organs are differentiated and immunoreactivity was observed in these organs, in both sensory cells and accessory cells. From day 30 after hatching, there was a regular decrease in the number of tuberous organs showing labelled accessory cells, and one hundred days later only 8% of tuberous organs had immunoreactive accessory cells. The adult accessory cells were no longer labelled with anti-SP antiserum. The results showed that in Apteronotus leptorhynchus, the epidermal structures which give rise to the cutaneous sensory organs were immunoreactive at a very early stage of development; this suggests that SP could have an effect upon their differentiation.     

The respiratory system of the genusCallithrix,the South American monkey

It has been described the cytology of the following parts of the respiratory system of some South American primates:Callithrix jacchus andCallithrix argentata melanura. The nasal cavities are divided into three parts: a vestibule, covered with a stratified nonkeratinized squamous epithelium; the respiratory portion, consisting of a pseudostratified columnar ciliated epithelium with goblet cells and the olfactory portion which is also covered with a high respiratory epithelium without goblet cells. The trachea is lined with a mucous membrane, whose epithelium is pseudostratified columnar ciliated with scarce goblet cells in the proximal portion unlike to the distal one. In the dorsal portion of the trachea, at the level of the gap between the two ends of incomplete cartilaginous rings, the epithelial lining is of transitional type. The incomplete hyaline cartilaginous rings present centers of calcification. The right and left lungs consist of two and three lobes respectively characteristic for these species, but they are not divided into lobules by connective tissue as in other ones. The bronchi, bronchioles and the respiratory portion, respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli present the typical respiratory structure with exception of their cartilaginous configuration; the cartilage continues as far as the respiratory bronchioles and alveolar ducts. These last structures are formed by a thin squamous epithelium, in which we observed two types of alveolar lining cells. This work was supported by grants from the Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET) and EHIGE program. Postgraduated fellow from CONICET. established Investigator and Director of EHIGE (Estudio Histológico comparado del Sistema de Glándulas Endócrinas) from CONICET.     

Pollution and tidal benthic communities of the James River Estuary,Virginia

Distribution of benthic communities in the estuarine portion of the James River was controlled mainly by salinity. Pollution effects were localized and difficult to assess because of a rigorous physical environment. Mesohaline and oligohaline communities were very similar to those in other estuaries of the eastern United States. Macrobenthic densities were most severely depressed in tidal freshwater habitats near Richmond & Hopewell, where the major portion of the pollution load enters the river. Cluster analysis of species distributional patterns and ordination of pollution and physical parameters produced similar results, dividing the river into mesohaline, oligohaline, and upper and lower tidal freshwater zones. Further analysis of only the tidal freshwater portion indicated the distribution of benthic communities reflected the location and concentration of pollution sources along the river. Tidal freshwater communities were dominated by the Asiatic clam, Corbicula fluminea, tubificid oligochaetes of the genus Limnodrilus and the chironomid insect larva Coelotanypus scapularis. The fauna of the freshwater zones was very eurytopic with respect to sediment type and has a great resemblance to the fauna of eutrophic lakes. The classical concept of a sharp increase in number of species occurring from oligohaline to freshwater zones was found to be misleading. This increase does not occur until free flowing (or lotic) freshwater areas of greater habitat diversity are reached.     

Proteome analysis of Pueraria mirifica tubers collected in different seasons

Pueraria mirifica-derived tuberous powder has been long-term consumed in Thailand as female hormone-replacement traditional remedies. The protein profiles of tubers collected in different seasons were evaluated. Phenol extraction, 2D-PAGE, and mass spectrometry were employed for tuberous proteome analysis. Out of the 322 proteins detected, over 59% were functionally classified as being involved in metabolism. The rest proteins were involved in defense, protein synthesis, cell structure, transportation, stress, storage, and also unidentified function. The proteins were found to be differentially expressed with respect to harvest season. Importantly, chalcone isomerase, isoflavone synthase, cytochrome p450, UDP-glycosyltransferase, and isoflavone reductase, which are all involved in the biosynthesis pathway of bioactive isoflavonoids, were most abundantly expressed in the summer-collected tubers. This is the first report on the proteomic patterns in P. mirifica tubers in relevant with seasonal variation. The study enlights the understanding of variance isoflavonoid production in P. mirifica tubers.     

Ultrastructure and histochemistry of the male reproductive system of the genus Callinectes Stimpson, 1860 (Brachyura: Portunidae)

We described the ultrastructure and histochemistry of the reproductive system of five Callinectes species, and evaluate the seasonal variation in weight of the reproductive system and hepatopancreas by comparing annual changes of somatic indices. The somatic indices changed little throughout the year. In Callinectes, spermatogenesis occurs inside the lobular testes and, within each lobule, the cells are at the same developmental stage. Spermatogenesis and spermiogenesis follow the same development pattern in all Callinectes studied. Mature spermatozoa are released into the seminiferous ducts through the collecting ducts. Cells of the vas deferens are secretory as evidenced by rough endoplasmic reticulum, Golgi complex, and secretory vesicles that produce the seminal fluid. The anterior vas deferens shows two portions: proximal and distal. In proximal portion (AVDp), spermatozoa are clustered and embedded in an electron-dense, basophilic glycoproteinaceous secretion Type I. In the distal portion (AVDd), the spermatophore wall is formed by incorporation of a less electron-dense glycoproteinaceous secretion Type II. The secretion Type I change to an acid polysaccharide-rich matrix that separates the spermatophores from each other. The median vas deferens (MVD) stores the spermatophores and produces the granular glycoproteinaceous seminal fluid. The posterior vas deferens (PVD) has few spermatophores. Its epithelium has many mitochondria and the PVD seminal fluid changes into a liquid and homogeneous glycoprotein. Many outpocketings in the PVD and MVD help to increase the fluid production. Overall, the reproductive pattern of Callinectes is similar to other species that produce sperm plugs. The secretions of AVD, MVD, and PVD are responsible for the polymerization that forms the solid, waxy plug in the seminal receptacle. The traits identified here are common to all Portunidae species studied so far.     

SPERMATOGENESIS IN A HOMOSPOROUS FERN,ONOCLEA SENSIBILIS

A detailed study of spermatogenesis in a homosporous fern, Onoclea sensibilis L., is presented from the formation of the first spermatogenous cell to the release of the sperm. Two different walls are deposited around the developing spermatids at specific developmental stages as opposed to one wall reported for other species. Most ultrastructural changes that occur in Onoclea during spermatid differentiation resemble those described in previous studies on other fern species, with the following exceptions: 1) A previously undescribed structure appears during midspermatid stage. This dense layer of amorphous material with a row of evenly spaced light areas occurs between the anterior portion of the mitochondrion associated with the multilayered structure and the anterior plasmalemma of the spermatid. 2) An early stage in blepharoplast formation resembles that which occurs in the heterosporous fern Marsilea, in contrast to that which has been reported in Platyzoma, the only other homosporous fern studied at this stage. 3) The osmiophilic crest does not form as early as reported in other ferns. 4) The cap cell of Onoclea is removed intact, rather than collapsing or forming a pore during sperm release. Observations are reported on the number of sperm per antheridium, the time course of spermatogenous cell mitosis, and of differentiation of spermatids into sperm. In Onoclea, an antheridium may contain either 32 or 64 sperm. Regardless of the final number of sperm, each has approximately the same volume.     

The Reproductive System of Gastrotrichs. I Introduction with morphological data for two new Dolichodasys species1

This paper begins a series aimed at clarifying the structure and function of reproductive organs in Gastrotricha Macrodasyida. Morphological data are presented for Dolichodasys carolinensis sp.n. and D. delicatus sp.n. Both are elongate, have reduced adhesive organs and complex accessory reproductive organs, termed the frontal-caudal organ system. The system consists of a band of cells behind the gonads in the central body chamber. The anterior portion, the frointal organ, stores foreign spermatozoa; the posterior portion, the caudal organ, may function as a copulatory organ. The caudal organ has two canals forming a loop opening at a single ventral pore. One canal contains a spiralled secretion, the other elongated filaments that appear to be muscle cell derivatives. Systematic groupings are made for other long-bodied Gastrotricha Macrodasyida.     

牛大力块根糖积累及其相关酶活性变化研究

为提高牛大力块根的产量与品质,该研究以不同发育时期(移栽6、12、18、24、30、36个月)的牛大力块根为材料,采用紫外分光光度法对糖类含量及其相关酶活性进行测定,研究它们在牛大力块根发育过程中的动态变化规律。结果表明:(1)牛大力块根的生长发育进程可初步划分为形成期(移栽6～12个月)、迅速膨大期(移栽12～24个月)与稳定膨大期(移栽24～36个月)三个阶段。淀粉与蔗糖分别是牛大力块根中主要的多糖与可溶性糖。在牛大力块根发育过程中,多糖类物质的含量逐渐增加,而可溶性糖含量逐渐减少,两者之间呈显著负相关,推测可溶性糖的分解代谢有利于促进多糖类物质的积累。(2)蔗糖的分解代谢是蔗糖合酶(SUS)、蔗糖磷酸合酶(SPS)、酸性转化酶(AI)与中性转化酶(NI)等多种相关酶协同作用的结果。SUS在牛大力块根发育过程中发挥着既催化蔗糖合成,又催化蔗糖分解的双重调节作用,SUS(合成)的活性不断上升,至移栽36个月达到峰值,极显著高于其他时期; SUS(分解)的活性从移栽6个月至24个月逐渐上升,但在块根稳定膨大期稍有下降; 其净活性为催化蔗糖分解,在移栽12个月达到最高。转化酶AI和NI的活性均在块根发育过程中逐渐上升,且AI活性高于NI活性,提示AI可能在蔗糖代谢分解过程中发挥更重要的作用。该研究结果可为今后深入研究牛大力多糖类成分积累和调控机制提供理论依据,并为提高牛大力药材的产量与品质提供技术指导。     

Characterization of a Kinesin-Related Gene ATSV, within the Tuberous Sclerosis Locus (TSC1) Candidate Region on Chromosome 9Q34

In the search for candidate genes for the tuberous sclerosis (TSC1) disease locus on chromosome 9q34, we have isolated an overlapping series of 22 plasmid and phage cDNA clones covering nearly 7 kb and with an open reading frame of 5070 bp encoding a protein of 1690 amino acids. The putative protein product is a member of the kinesin superfamily and is homologous to the mouse KIF1A and theCaenorhabditas elegansunc-104 genes. Both KIF1A and unc-104 function in the anterograde axonal transport of synaptic vesicles. The human homolog is therefore termed H-ATSV (axonal transporter of synaptic vesicles, HGMW-approved nomenclature ATSV) Screening of DNA from 107 tuberous sclerosis patients and 80 unaffected individuals with H-ATSV cDNA probes by pulsed-field gel electrophoresis/Southern blotting following digestion by rare-cutting methylation-sensitive restriction enzymes showed variant banding patterns in three patients with tuberous sclerosis. However, further analysis indicated that these variant fragments represent a rare polymorphism probably associated with methylation of clustered restriction sites. There is no evidence to support H-ATSV as a candidate gene for TSC1.