Results 181 to 190 of about 4,495 (224)

Piwi expression in archeocytes and choanocytes in demosponges: insights into the stem cell system in demosponges

Evolution & Development, 2010
SUMMARY Little is known about the stem cells of organisms early in metazoan evolution. To characterize the stem cell system in demosponges, we identified Piwi homologs of a freshwater sponge, Ephydatia fluviatilis, as candidate stem cell (archeocyte) markers. EfPiwiA mRNA was expressed in cells with archeocyte cell morphological features.
N. Funayama, M. Nakatsukasa, Kurato Mohri, Y. Masuda, K. Agata   +4 more
semanticscholar   +3 more sources

Biomineralization in living hypercalcified demosponges: toward a shared mechanism?

Journal of Structural Biology, 2013
Massive skeletons of living hypercalcified sponges, representative organisms of basal Metazoa, are uncommon models to improve our knowledge on biomineralization mechanisms and their possible evolution through time. Eight living species belonging to various orders of Demospongiae were selected for a comparative mineralogical characterization of their ...
M. Gilis, O. Grauby, P. Willenz, P. Dubois, V. Heresanu, A. Baronnet   +5 more
semanticscholar   +4 more sources

Recycling resources: silica of diatom frustules as a source for spicule building in Antarctic siliceous demosponges

Zoological Journal of the Linnean Society, 2020
Dissolved silicon (DSi) is biologically processed to produce siliceous skeletons by a variety of organisms including radiolarians, silicoflagellates, choanoflagellates, plants, diatoms and some animals.
A. Riesgo, S. Taboada, N. Kenny, Nadia Santodomingo, J. Moles, Carlos Leiva, E. Cox, C. Ávila, L. Cardona, M. Maldonado   +9 more
semanticscholar   +1 more source

Nanostructural features of demosponge biosilica

Journal of Structural Biology, 2003
Recent interest in the optical and mechanical properties of silica structures made by living sponges, and the possibility of harnessing these mechanisms for the synthesis of advanced materials and devices, motivate our investigation of the nanoscale structure of these remarkable biomaterials. Scanning electron and atomic force microscopic (SEM and AFM)
James C, Weaver, Lía I, Pietrasanta, Niklas, Hedin, Bradley F, Chmelka, Paul K, Hansma, Daniel E, Morse   +5 more
openaire   +2 more sources

Development in primary cell culture of demosponges

Journal of Biotechnology, 2003
We have established primary cell culture of the marine demosponge Dysidea avara and Suberites domuncula. Microbial contamination was controlled by the use of a pool of antibiotics confirming the goodness of this procedure. Effect of pH, temperature and light was studied to establish the better growth conditions.
De Rosa Salvatore, De Caro Salvatore, Iodice Carmine, Tommonaro Giuseppina, Stefanov Kamen, Popov Simeon   +5 more
openaire   +5 more sources

Silica Deposition in Demosponges

2003
Demosponges are the most widespread class of the phylum Porifera. They secrete siliceous (spicules) and proteinaceous (fibers) elements, which constitute the skeleton that shapes the sponge growth and allow cell organization and establishment of the aquiferous system through which the surrounding water accesses the internal cells.
Maria J, Uriz, Xavier, Turon, Mikel A, Becerro   +2 more
openaire   +2 more sources

New early Cambrian sponges of the Siberian platform and the origins of spiculate crown‐group demosponges

Papers in Palaeontology
Sponges are among the most common and diverse Cambrian fossils. However, the origin of the crown groups of the extant sponge classes constitutes the principal problem in the understanding of the evolution of these lower metazoans.
K. A. Kolesnikov, J. Botting, A. Ivantsov, A. Y. Zhuravlev   +3 more
semanticscholar   +1 more source

Mesostructure from Hydration Gradients in Demosponge Biosilica

Chemistry – A European Journal, 2014
AbstractOrganisms of the phylum Porifera, that is, sponges, utilize enzymatic hydrolysis to concatenate bioavailable inorganic silicon to produce lightweight, strong, and often flexible skeletal elements called spicules. In their optical transparency, these remarkable biomaterials resemble fused silica, despite having been formed under ambient marine ...
James R, Neilson, Nathan C, George, Meredith M, Murr, Ram, Seshadri, Daniel E, Morse   +4 more
openaire   +2 more sources

Siliceous spicules in marine demosponges (example Suberites domuncula)

Micron, 2006
All metazoan animals comprise a body plan of different complexity. Since--especially based on molecular and cell biological data--it is well established that all metazoan phyla, including the Porifera (sponges), evolved from a common ancestor the search for common, basic principles of pattern formation (body plan) in all phyla began.
Werner E G, Müller, Sergey I, Belikov, Wolfgang, Tremel, Carole C, Perry, Winfried W C, Gieskes, Alexandra, Boreiko, Heinz C, Schröder   +6 more
openaire   +2 more sources

Genetic data confirms the enigmatic demosponge Janulum as haplosclerid

Zootaxa, 2023
Historically, sponge classification is based on the interpretation of morphological characters, whose phylogenetic information content is frequently limited, subject to homoplasies, or prone to environmental plasticity (e.g., Chombard et al. 1998). Therefore, the currently accepted order-level classification of its largest class, Demospongiae, has been
DIRK ERPENBECK, ROB W.M. VAN SOEST, GERT WÖRHEIDE, MICHELLE KELLY   +3 more
openaire   +2 more sources