ASCIDIAN NEWS*

Gretchen and Charles Lambert

12001 11th Ave. NW, Seattle, WA 98177

206-365-3734

glambert@fullerton.edu or clambert@fullerton.edu

home page:  http://depts.washington.edu/ascidian/

 

Number 58                                                                                                            December 2005

 

   We spent part of the summer in Santa Barbara where Gretchen worked at the Natural History Museum with Eric Hochberg identifying the ascidians in the collection and added a large part of her personal collection. Charlie worked in Kathy Foltz’s lab at UCSB on germinal vesicle breakdown in Styela clava oocytes. We also attended the 3rd Intl. Tunicate Conference there in mid-July. Many colleagues attended, and we had the pleasure of meeting a number of others we had known only from their publications. After returning to Seattle, Gretchen participated in a rapid assessment survey of the Eastport, Maine area sponsored by the Nature Conservancy (see article in the Winter 2005 issue). We then traveled to Roscoff in Brittany, France to join John Bishop and his postdoc Lise Dupont with whom we surveyed a number of harbors for non-native ascidians and helped them collect tissue for DNA analysis from Styela clava, Perophora japonica and Corella eumyota. John, Lise and Frederique Viard also surveyed the harbors on Guernsey island with Richard Lord. After the survey we rented a car and toured the Alsace-Lorraine region. Gretchen continues her work with the Dept. of Fish and Wildlife and Washington Sea Grant, monitoring the distribution of Styela clava and Didemnum sp. A in Puget Sound.  In October we presented an ascidian identification workshop at the Pacific Biological Station in Nanaimo, British Columbia.  This workshop included mostly govt. employees and workers involved in shellfish aquaculture which is plagued by heavy fouling by Didemnum sp. A and Botrylloides violaceus and a few S. clava. Immediately after the workshop we participated with Sea Grant in an unsuccessful attempt to eradicate S. clava from a harbor in the Hood Canal, Washington. Gretchen keeps busy identifying ascidians for the Smithsonian Institution and the state of California.

   This AN includes 118 new publications on the Tunicata!  Keep up the good work and to assure that your new publications will appear in AN please don’t forget to send us hard copy reprints (preferred especially if they contain color figs as we do not have a color printer) or PDFs; thank you.

 

*Ascidian News is not part of the scientific literature and should not be cited as such.

 

NEWS AND VIEWS

 

1. First announcement of 2007 Tunicata meeting From Christian Sardet, Station Zoologique, Observatoire, CNRS, Univ PM Curie, Villefranche sur Mer 06230, France   christian.sardet@obs-vlfr.fr

   As discussed at Santa Barbara's 3rd Intl. Tunicate Conference, we investigated possibilities to hold the next meeting (2007) in the Villefranche sur Mer area end of June or early October 2007.

We found a suitable site to organize a 4 day meeting (arriving Saturday, leaving Wednesday) at the Residence Delcloy in St Jean Cap Ferrat and hope to keep the expenses to below 400 Euros (about 450 actual US Dollars, including room, full board and meals, registration). You can see the meeting place: http://biodev.obs-vlfr.fr/recherche/biomarcell/films%2Bimages/ResidenceDlcloy.html

and a Map of the area: http://biodev.obs-vlfr.fr/recherche/biomarcell/images/R%E9sidence%20DELCLOY/MapResidenseDelcloy.jpg

To plan ahead and firmly reserve the place it would be helpful if you fill out the questionnaire below

1) WOULD YOU PARTICIPATE AND PRESENT YOUR WORK.

2) WHEN WOULD YOU PREFER THE MEETING TO BE HELD: Last week of June? Early October?

3) HOW MANY LAB MEMBERS WOULD YOU BRING?

4) WOULD YOU COME ACCOMPANIED (SPOUSE, CHILDREN?)

5) COMPARED WITH 2003/2004 EDITIONS IN MARSEILLE AND 2005 EDITION IN SANTA BARBARA, DO YOU HAVE SUGGESTIONS ABOUT NEW TOPICS / ORGANISATIONAL QUESTIONS.

 

Please visit the Sardet lab website for downloadable PDFs of new publications and posters, and the BioClips site http://www.bioclips.com/ showing 40 multimedia documents highlighted by Science NetWatch containing several documents dealing with research on ascidians.

http://biodev.obs-vlfr.fr/recherche/biomarcell/

 

2. From Dr. Gabriel Gorsky: New book: Response of Marine Ecosystems to Global Change—Ecological Impact of Appendicularians. Edited by G. Gorsky, M. J. Youngbluth and D. Deibel. “Almost everything you wanted to know about appendicularians but were afraid to ask is discussed in this book or in the references herein. Although these free swimming tunicates are the most primitive chordates, having the smallest chordate genome known, they developed one of the most complex external food concentrating mucous structure and using tangential filtration they feed efficiently on sub-micron and micron sized particles. The nearly 70 known species are adapted to all the oceanic environments including the deep sea and make a significant contribution to what is called

marine snow: slowly sedimenting marine particles and thus to the carbon cycling. Chapter after chapter reviews the latest findings in the fields of phylogenetics, diversity, reproduction, nutritional biology, population dynamics, carbon flux and predator-prey relationships.” (quoted from the publisher)

CONTACT LIBRAIRIE PHILOSOPHIQUE J.VRIN     contact@vrin.fr

6, PLACE DE LA SORBONNE, 75005 PARIS, FRANCE

TEL: +33 (0)1 43 54 03 47 — FAX: +33 (0)1 43 54 48 18

 

3. Check out the fabulous newly-released GUIDE TO EXOTIC SPECIES for San Francisco Bay, created by Dr. Andrew Cohen (acohen@sfei.org) of the San Francisco Estuary Institute. http://www.exoticsguide.org  We have added a link to it on the Ascidian News homepage. It was highlighted in SCIENCE Vol. 309 22 July 2005, p. 539: “More than 175 alien species have settled in the bay’s waters, making it one of the world’s hot spots for aquatic invaders. Meet many of these troublemakers at a new guide from the San Francisco Estuary Institute in Oakland. The guide aims to help researchers and the general public identify and monitor invasive species. You can consult detailed profiles on new colonists such as the star sea squirt (Botryllus schlosseri) [NOT new—AN eds.], a European native, and the parasitic flatworm Austrobilharzia variglandis from the northern Atlantic Ocean. This pesky worm can incite a rash called swimmer’s itch in people who contact it. “This is one of the first cases where we can document that an introduced species is negatively impacting public health” in the Bay area, says site creator Andrew Cohen. He hopes to enlarge the guide to incorporate all the invasive species that have taken up residence along the West Coast.”

  Only 4 ascidian species are covered at this point: Botrylloides violaceus, Botryllus schlosseri, Didemnum sp. A and Styela clava: excellent photos and well written descriptions are included for all of them.

 

4. There have been a number of interesting email exchanges on edible ascidians lately on the Tunicata listserv; you can go to the website and click on the Archives and then on November and December 2005. There you will find a few recipes, photos of ascidians for sale at markets in various countries, and websites with photos and descriptions of methods of culturing ascidians. Click on November and December 2005 to get a list of the emails. Click on the email title to open it (black underlined lettering). The larger size emails contain photos. Tito Lotufo sent in an interesting Chilean recipe for mussel and Pyura stew (Nov. 30). The email from Shota Chiba on 29 November contains a website on culturing Halocynthia roretzi in Korea: http://www.lib.noaa.gov/korea/main_species/sea_squirt.htm

Shogo Kajiwara (3 December email) made a website on culturing H. roretzi in Japan: http://fen.edu.iwate-u.ac.jp/~rika/biology/kaji/hoya/index-e.html

If you have not yet joined the Tunicata email discussion forum, it is easy to do so at http://www.jiscmail.ac.uk/lists/tunicata.html though you do not need to join in order to view the emails.

 

WORK IN PROGRESS

 

1. Offspring size effects mediate competitive interactions in a colonial marine invertebrate. Dustin J. Marshall, Carly N. Cook and Richard B. Emlet. Ecology in press.

  Abstract: Over the past 30 years, numerous attempts to understand the relationship between offspring size and fitness have been made, and it has become clear that this critical relationship is strongly affected by environmental heterogeneity. For marine invertebrates, there has been a long standing interest in the evolution of offspring size, but there have been very few empirical and theoretical examinations of post-metamorphic offspring size effects and almost none have considered the effect of environmental heterogeneity on the offspring size/fitness relationship.We investigated the post-metamorphic effects of offspring size in the field for the colonial marine invertebrate Botrylloides violaceus. We also examined how the relationship between offspring size and performance was affected by three different types of intraspecific competition. We found strong and persistent effects of offspring size on survival and growth but these effects depended on the level and type of intraspecific competition. Generally, competition strengthened the advantages of increasing maternal investment. Interestingly, we found that offspring size determined the outcome of competitive interaction: juveniles that had more maternal investment were more likely to encroach on another juvenile’s territory. This suggests that mothers have the previously unrecognized potential to influence the outcome of competitive interactions in benthic marine invertebrates. We created a simple optimality model, which utilized the data generated from our field experiments and found that increasing intraspecific competition resulted in an increase in predicted optimal size. Our results suggest that the relationship between offspring size and fitness is highly variable in the marine environment and strongly dependent on the density of conspecifics.

 

2. Ca2+ and Na+ current patterns during oocyte maturation, fertilization and early developmental stages of Ciona intestinalis. Annunziata Cuomo,  Francesco Silvestre,  Rosaria De Santis,  Elisabetta Tosti.  tosti@szn.it  Laboratory of Cell Biology, Stazione Zoologica , 80121 Napoli, Italy  Molecular Reproduction and Development  in press.

ABSTRACT: Using the whole-cell voltage clamp technique, the electrical changes in oocyte and embryo plasma membrane were followed during different meiotic and developmental stages in Ciona intestinalis. We show, for the first time, an electrophysiological characterization of the plasma membrane in  oocytes at the germinal vesicle (GV) stage with high L-type calcium (Ca2+) current activity that decreased through meiosis. Moreover, the absence of Ca2+ reduced germinal vesicle breakdown (GVBD), which is consistent with a role of Ca2+ currents in the prophase/metaphase transition.  In mature oocytes at the metaphase I (MI) stage, Ca2+ currents decreased and then disappeared and sodium (Na+) currents first appeared remaining high up to the zygote stage.  Intracellular Ca2+  release was higher in MI than in GV, indicating that  Ca2+ currents in GV may contribute to fill the stores which are essential for oocyte contraction at fertilization. The fertilization current  generated in Na+ free sea water was significantly lower than the control; furthermore, oocytes fertilized in the absence of Na+ showed high development of  anomalous “rosette” embryos. Current amplitudes became negligible in embryos at the 2- and 4-cell stage, suggesting that signalling pathways that mediate first cleavage do not rely on ion current activities. At the 8-cell stage embryo, a resumption of  Na+ current activity and conductance occurred, without a correlation with specific blastomeres. Taken together, these results imply: i) an involvement of L-type Ca2+ currents in meiotic progression from the GV to MI stage;  ii) a role of Na+ currents during electrical events at fertilization and subsequent development; iii)  a major role of plasma membrane permeability and a minor function of specific currents during initial cell line segregation events.

 

ABSTRACTS FROM RECENT MEETINGS

 

 [Unfortunately the list of participants and abstracts are not available for the 3rd Intl. Tunicate Conference that was held in Santa Barbara, Calif. July 9-13.]

 

1. Ninth SCAR Intl. Biology Symposium 25-31 July, 2005, Curitiba (Brasil).

Benthic tunicates (Urochordata) from Bellingshausen Sea and Antarctic Peninsula (Western Antarctica). Juan Cárcel, M. Mercedes Varela and Alfonso A. Ramos-Esplá. Dept. Marine Sci. and Applied Biol., Univ. of Alicante, E-03080 Alicante (Spain). Alfonso.Ramos@ua.es

   Bellingshausen Sea represents one of the less known areas of the Antarctic waters from the benthic fauna taxa. The Spanish research cruise Bentart-2003 in February-March 2003 has enlarged the knowledge of the benthic Tunicata from littoral and bathial bottoms (0 to 2200m depth), sampled by Agassiz trawl, rocky dredge, box-corer and scuba diving on hard and soft substrata. About 1200 specimens belonging to 40 species have been determined. These fauna participated from the Antarctic region and Subantarctic islands, and some interesting species, as Sorberacea group, have been sampled. The paper contributes to the taxonomic, ecological and biogeographical knowledge of this important group (in number and biomass) in the Western Antarctica.

 

2 Society for Developmental Biology Meetings, San Francisco,  July 27-31, 2005.

Nodal Signaling and the Evolution of Deuterostome Gastrulation.  Helen K. Chea and Billie J. Swalla, Dept. of Biology, Univ. of Washington, Seattle, WA. bjswalla@u.washington.edu  Develop. Biol. 283: 650 #369

   Deuterostomes are animals in which the blastopore becomes the anus and the mouth forms secondarily in another location during embryonic development. The evolution of gastrulation within the deuterostomes has allowed for the formation of the various developmental and morphological differences seen in larval and adult deuterostomes today. Although gastrulation is an amazingly complicated developmental process, involving wide-scale cell movements and signaling mechanisms, there are some common mechanisms that are beginning to emerge. An important signaling pathway involved in regulating gastrulation is that of nodal. Nodal is a member of the transforming growth factor-ъ (TGF-ъ) superfamily of signaling molecules, and it plays a regulatory role in cell interactions that are responsible for patterning the early embryo. Nodal was initially discovered in vertebrates, but has also been found in invertebrate chordates and, most recently, in non-chordate deuterostomes. We examine nodal expression in each of the vertebrate model systems, then compare them to the invertebrate deuterostomes. When Nodal expression within the deuterostomes is examined, several conserved features emerge. We have also conducted experiments to determine when and where Nodal is expressed throughout tunicate development, in order to understand how Nodal signaling has evolved in the chordates. Nodal is expressed early during gastrulation and later to specify left-right asymmetry in chordates, but the ancestral role of Nodal may have been in positioning the mouth during larval and/or adult development.

 

3. Intl. Meeting of the Latin American Society for Dev. Biol., Guaruja, Brazil; May 4-7, 2005.  Tracking the germ cells in ascidians. Federico D. Brown and Billie J. Swalla, Dept. of Biology, Univ. of Washington, Seattle, WA. and Friday Harbor Laboratories, Friday Harbor, WA.  fdbrown@u.washington.edu  Federico won a "Student Best Poster" Award at the meeting.

   The germline in metazoans is specified either immediately after fertilization by maternal determinants, or by a pluripotent stem cell lineage set aside later in development. The solitary ascidian Ciona intestinalis segregates a germline that becomes localized in the endodermal strand cells of the tail at the tadpole stage. Paradoxically, experimental studies of tail ablation, which deleted germ line cells, have been reported to generate new germ cells. I  have compared the expression of Ciona vasa, a DEAD box RNA helicase found in germ cells across the metazoans, to the localization of vasain the solitary ascidian Boltenia villosa, and to the expression in adult colonies of the ascidian Botrylloides violaceus. In the solitary ascidian B. villosa, in situ hybridization studies have shown strong expression of vasa in the small germ cells of the adult gonad. Boltenia vasa mRNA is strongly expressed in the cytoplasm and nuclei of small oocytes in the gonad and expression decreases qualitatively in larger oocytes, where it is observed within and around the germinal vesicle. During gastrulation, vasa expression was restricted to a few posterior cells of the embryo, similar to Ciona. Preliminary data using a fly vasa polyclonal antibody to identify germ cells, suggests a putative second population of Primordial Germ Cells (PGCs) in the head of the larval tadpole of the solitary ascidian Boltenia villosa. At least three different mechanisms can be proposed to explain the repopulation of  PGCs in tail-ablated solitary ascidians: 1) a pluripotent stem cell lineage is present in solitary ascidians that can give rise to new PGCs; 2) a dedifferentiation process of somatic stem cells can occur to give rise to new PGCs; and 3) an alternative source of germ line stem cells is present in the tadpole head. In the colonial ascidan B. violaceus, in situ hybridization of adult colonies revealed mRNA expression in presumptive gonads of budding zooids, and in certain isolated cells in the differentiating zooid. The timing of specification of the germline in colonial ascidians and the functionality of these vasapositive cells in adult colonies remain unknown.

 

4. 3rd Intl. Tunicata Conference, Santa Barbara, CA July 9-13, 2005.

Activation of ascidian oocyte maturation: Effects of various enzyme agonists and antagonists on germinal vesicle breakdown. Charles C. Lambert, Univ. of Washington Friday Harbor Labs, Friday Harbor, WA  clambert@fullerton.edu

   Previous work on the onset of oocyte maturation (germinal vesicle breakdown,  GVBD) in ascidians had been investigated in Halocynthia roretzi  (Pyuridae), in which GVBD commences shortly after the oocyte is removed from the ovary and suspended in SW. The signaling pathways involved in GVBD remain unknown.  Herdmania pallida (Pyuridae) functions like H. roretzi; GVBD occurs on contact with seawater. Oocytes of Cnemidocarpa irene (Styelidae) do not spontaneously undergo GVBD in SW but may be activated by external agents. [Dev. Growth & Differ. 47:265-272, 2005]. Herdmania, Boltenia, Pyura and Styela oocytes are all activated by contact with SW but inhibited from GVBD by pH 4 SW. They can subsequently be activated by mastoparan (G-protein activator), A23187 (Ca2+ ionophore) or dimethylbenzanthracene (tyrosine kinase activator). These same reagents induce GVBD in pH 8 Cnemidocarpa irene oocytes. This requires maturation promoting factor (MPF) activity; cyclin-dependent kinase inhibitors roscovitine and olomoucine are inhibitory to Herdmania and Cnemidocarpa maturation.  The activation process appears to involve an increase in intracellular cAMP levels as permeant 8-bromo cAMP activated GVBD at 4 mM in a dose dependent manner. Forskolin, an activator of adenylyl cyclase, induced GVBD at micromolar concentrations. Phosphodiesterase inhibitors such as theophylline caused GVBD with a maximal response at 0.5 µm; caffeine, hypoxanthine and isobutyl methylxanthine also caused GVBD at low concentrations. These studies strongly implicate increased intracellular cAMP levels in GVBD of ascidian oocytes as is the case in hydrozoans, ophiuroids and nemerteans. This is an unusual finding, as cAMP inhibits GVBD in most other deuterostomes including vertebrates and asteroids. Studies are now underway to measure cAMP levels within the oocyte during maturation.

 

NEW PUBLICATIONS 

 

Anon. 2005. Ascidians (Tunicata, Ascidiacea) from the Arvoredo Marine Biological Reserve, Santa Catarina, Brazil. Revista Brasileira de Zool. 22: 461-476.

Azumi, K., Sasaki, T., Okochi, K., Yamasaki, S., Saito, T., Takayama, H. and Yokosawa, H. 2005. Differential display analysis reveals the expression of glutathione S-transferase omega and novel genes through an ITAM-containing receptor in ascidian immunocytes. Immunogenetics 57: 444-452.

Ballarin, L. and Cima, F. 2005. Cytochemical properties of Botryllus schlosseri haemocytes: indications for morpho-functional characterisation. Eur. J. Biochem. 49: 255-264.

Ban, S., Harada, Y., Yokosawa, H. and Sawada, H. 2005. Highly polymorphic vitelline-coat protein HaVC80 from the ascidian, Halocynthia aurantium: Structural analysis and involvement in self/nonself recognition during fertilization. Dev.  Biol. 286: 440-451.

Bassham, S. and Postlethwait, J. 2005. The evolutionary history of placodes: a molecular genetic investigation of the larvacean urochordate Oikopleura dioica. Development online 24 August: 4259-4272.

Brena, C., Cima, F., Martinucci, G. and Burighel, P. 2005. The appendicularian alimentary tract: a comparative study. In: Gorsky, G., Youngbluth, M. J. and Deibel, D. (ed.), Response of Marine Ecosystems to Global Change: Ecological Impact of Appendicularians. Paris, Contemporary Publishing Intl., pp. 161-170.

Cañestro, C., Bassham, S. and Postlethwait, J. 2005. Development of the central nervous system in the larvacean Oikopleura dioica and the evolution of the chordate brain. Dev.  Biol. 285: 298 – 315.

Chavanich, S., Koeysin, P., Viyakarn, V., Piyatiratitivorakul, S., Menasveta, P., Suwanborirux, K. and Poovachiranon, S. 2005. A tunicate from a Thai coral reef: a potential source of new anticancer compounds. Coral Reefs epub  24 October:

Chea, H. K., Wright, C. V. and Swalla, B. J. 2005. Nodal signaling and the evolution of deuterostome gastrulation. Dev. Dyn. 234: 269–278.

Cima, F., Ballarin, L., Gasparini, F. and Burighel, P. 2005. External amebocytes guard the pharynx entry in a tunicate (Ascidiacea). Dev. Comp. Immunol.; Epub. advance publication.

Cima, F., Brena, C., Martinucci, G. and Burighel, P. 2005. Gut histochemistry in Oikopleura dioica. In: Gorsky, G., Youngbluth, M. J. and Deibel, D. (ed.), Response of Marine Ecosystems to Global Change: Ecological Impact of Appendicularians. Paris, Contemporary Publishing Intl., pp. 149-159.

Cohen, A. N., Harris, L. H., Bingham, B. L., Carlton, J. T., Chapman, J. W., Lambert, C. C., Lambert, G., Ljubenkov, J. C., Murray, S. N., Rao, L. C., Reardon, K. and Schwindt, E. 2005. Rapid Assessment Survey for exotic organisms in southern California bays and harbors, and abundance in port and non-port areas. Biol. Invasions 7: 995-1002.

da Rocha, R. M. and Barros de Faria, S. 2005. Ascidians at Currais Islands, Paraná, Brazil: taxonomy and distribution. Biota Neotropica 5: 20 pp.; online journal.

da Rocha, R. M., Moreno, T. R. and Metri, R. 2005. Ascidias (Tunicata, Ascidiacea) da Reserva Biológica Marinha do Arvoredo, Santa Catarina, Brazil. Revista Brasileira de Zool. 22: 461-476.

Davidson, B., Shi, W. and Levine, M. 2005. Uncoupling heart cell specification and migration in the simple chordate Ciona intestinalis. Development 132: 4811-4818.

Di Bella, M. A., Carbone, M. C. and De Leo, G. 2005. Aspects of cell production in mantle tissue of Ciona intestinalis L. (Tunicata, Ascidiacea). Micron 36: 477-481.

Dias, G., Duarte, L. and Solferini, V. 2005. Low genetic differentiation between isolated populations of the colonial ascidian Symplegma rubra Monniot, C. 1972. Mar. Biol. 28 Sept.:

Dupont, L., Viard, F. and Bishop, J. D. D. 2005. Isolation and characterization of twelve polymorphic microsatellite markers for the invasive ascidian Styela clava (Tunicata). Molec. Ecol. Notes

Edvardsen, R. B., Seo, H. C., Jensen, M. F., Mialon, A., Mikhaleva, J., Bjordal, M., Cartry, J., Reinhardt, R., Weissenbach, J., Wincker, P. and Chourrout, D. 2005. Remodelling of the homeobox gene complement in the tunicate Oikopleura dioica. Curr. Biol. 15: 12-13.

Erk, M., Ruus, A., Ingebrigtsen, K. and Hylland, K. 2005. Cadmium accumulation and Cd-binding proteins in marine invertebrates-A radiotracer study. Chemosphere 61: 1651-1664.

Ewan, R., Huxley-Jones, J., Mould, A. P., Humphries, M. J., Robertson, D. L. and Boot-Handford, R. P. 2005. The integrins of the urochordate Ciona intestinalis provide novel insights into the molecular evolution of the vertebrate integrin family. BMC Evol. Biol. 5: 31.

Geraci, F. and Giudice, G. 2005. Mechanisms of Ca2+ liberation at fertilization. Biochem. Biophys. Res. Comm. 335: 265-269.

Gould, R. M., Morrison, H. G., Gilland, E. and Campbell, R. K. 2005. Myelin tetraspan family proteins but no non-tetraspan family proteins are present in the ascidian (Ciona intestinalis) genome. Biol. Bull. 209: 49-66.

Hamada, M., Wada, S., Kobayashi, K. and Satoh, N. 2005. Ci-Rga, a gene encoding an MtN3/saliva family transmembrane protein, is essential for tissue differentiation during embryogenesis of the ascidian Ciona intestinalis. Differentiation 73: 364-376.

Horie, T., Orii, H. and Nakagawa, M. 2005. Structure of ocellus photoreceptors in the ascidian Ciona intestinalis larva as revealed by an anti-arrestin antibody. J. Neurobiol. 65: 241-250.

Hughes, A. L. and Friedman, R. 2005. Loss of ancestral genes in the genomic evolution of Ciona intestinalis. Evol. & Dev. 7: 196-200.

Hughes, D. J. and al., e. 2005. Biofiltration and biofouling on artificial structures in Europe: the potential for mitigating organic impacts. Oceanogr. Mar. Biol. Ann. Rev. 43: 123-172.

Hughes, R. N. 2005. Lessons in modularity: the evolutionary ecology of colonial invertebrates. Sci. Mar. 69: 169-179.

Huhtala, M., Heino, J., Casciari, D., de Luise, A. and Johnson, M. S. 2005. Integrin evolution: insights from ascidian and teleost fish genomes. Matrix Biol. 24: 83-95.

Huxley-Jones, J., Apte, S. S. and Robertson, D. L. 2005. The characterisation of six ADAMTS proteases in the basal chordate Ciona intestinalis provides new insights into the vertebrate ADAMTS family. Int. J. Biochem. Cell Biol. 37: 1838-1845.

Inoue, Y., Ogasawara, M., Moroi, T., Satake, M., Azumi, K., Moritomo, T. and Nakanishi, T. 2005. Characteristics of NADPH oxidase genes (Nox2, p22, p47, and p67) and Nox4 gene expressed in blood cells of juvenile Ciona intestinalis. Immunogenetics 57: 520-34.

Ishibashi, T., Usami, T., Fujie, M., Azumi, K., Satoh, N. and Fujiwara, S. 2005. Oligonucleotide-based microarray analysis of retinoic acid target genes in the protochordate, Ciona intestinalis. Dev. Dyn. 233: 1571-1578.

Jiang, D. and Smith, W. C. 2005. Self- and cross-fertilization in the solitary ascidian Ciona savignyi. Biol. Bull. 209: 107-112.

Johnson, D. S., Zhou, Q., Yagi, K., Satoh, N., Wong, W. and Sidow, A. 2005. De novo discovery of a tissue-specific gene regulatory module in a chordate. Genome Res. 15: 1315-1324.

Khalturin, K., Kurn, U., Pinnow, N. and Bosch, T. C. 2005. Towards a molecular code for individuality in the absence of MHC: screening for individually variable genes in the urochordate Ciona intestinalis. Dev. Comp. Immunol. 29: 759-773.

Kobayashi, Y., Ohashi, M., Kawamura, K., Yubisui, T. and Fujiwara, S. 2005. An ascidian homologue of the gonadotropin-releasing hormone receptor is a retinoic acid target gene. Comp. Biochem. Physiol. B Biochem. Mol. Biol. 141: 274-280.

Kott, P. 2005. New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (Part 3). J. Nat. Hist. 39: 2409-2479.

Kourakis, M. J. and Smith, W. C. 2005. Did the first chordates organize without the organizer? Trends Genet. 21: 506-510.

Laird, D. J., Chang, W. T., Weissman, I. L. and Lauzon, R. J. 2005. Identification of a novel gene involved in asexual organogenesis in the budding ascidian Botryllus schlosseri. Dev. Dyn. 234: 997-1005.

Lambert, G., Faulkes, Z., Lambert, C. C. and Scofield, V. L. 2005. Ascidians of South Padre Island, Texas, with a key to species. Texas J. Sci. 57: 251-262.

Lapidot, Z. and Rinkevich, B. 2005. Development of panel of monoclonal antibodies specific to urochordate cell surface antigens. Mar. Biotechnol. 7: 532-539.

Lapidot, Z. and Rinkevich, B. 2005. Development of monoclonal antibodies specific to urochordate intracellular epitopes. Cell Biol. Intl. epub advance publication

Lievens, S. C. and Molinski, T. F. 2005. Sagittamides A and B. Polyacetoxy long-chain acyl amino acids from a didemnid ascidian. Org. Lett. 7: 2281-2284.

Liu, H. W., Fujiwara, T. and Nishikawa, T. 2005. Lissoclibadins 1-3, three new polysulfur alkaloids, from the ascidian Lissoclinum cf. badium. Tetrahedron 61: 8611-8615.

Lombard, F., Sciandra, A. and Gorsky, G. 2005. Influence of body mass, food concentration, temperature and filtering activity on the oxygen uptake of the appendicularian Oikopleura dioica. Mar. Ecol. Prog. Ser. 301: 149-158.

Long, P. F., Dunlap, W. C., Battershill, C. N. and Jaspars, M. 2005. Shotgun cloning and heterologous expression of the patellamide gene cluster as a strategy to achieving sustained metabolite production. ChemBioChem 6: 1760 – 1765.

López-Legentil, S., Dieckmann, R., Bontemps-Subielos, N., Turon, X. and Banaigs, B. 2005. Qualitative variation of alkaloids in color morphs of Cystodytes (Ascidiacea). Biochem. Syst. & Ecol. 33: 1107-1119.

López-Legentil, S., Ruchty, M., Domenech, A. and Turon, X. 2005. Life cycles and growth rates of two morphotypes of Cystodytes (Ascidiacea) in the western Mediterranean. Mar. Ecol. Prog. Ser. 296: 219-228.

Manni, L., Agnoletto, A., Zaniolo, G. and Burighel, P. 2005. Stomodeal and neurohypophysial placodes in Ciona intestinalis: insights into the origin of the pituitary gland. J. Exp. Zool. B: Mol. Dev. Evol. 304B: 324–339.

Marchenkov, A. and Boxshall, G. A. 2005. Three new species of Enterocola van Beneden, 1860 (Crustacea: Copepoda: Cyclopoida) from ascidian hosts. Syst. Parasitol. 61: 223-233.

Marshall, D. J., Cook, C. N. and Emlet, R. B. 2006. Offspring size effects mediate competitive interactions in a colonial marine invertebrate. Ecology 87: 246-257.

Martinucci, G., Brena, C., Cima, F. and Burighel, P. 2005. Synchronous spermatogenesis in appendicularians. In: Gorsky, G., Youngbluth, M. J. and Deibel, D. (ed.), Response of Marine Ecosystems to Global Change: Ecological Impact of Appendicularians. Paris, Contemporary Publishing Intl., pp. 113-123.

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