Abstract：
:The evolutionary divergence of cnidarian and bilaterian lineages from their remote metazoan ancestor occurred at an unknown depth in time before the Cambrian, since crown group representatives of each are found in Lower Cambrian fossil assemblages. We report here a variety of putative embryonic, larval, and adult microfossils deriving from Precambrian phosphorite deposits of Southwest China, which may predate the Cambrian radiation by 25-45 million years. These are most probably of cnidarian affinity. Large numbers of fossilized early planula-like larvae were observed under the microscope in sections. Though several forms are represented, the majority display remarkable conformity, which is inconsistent with the alternative that they are artifactual mineral inclusions. Some of these fossils are preserved in such high resolution that individual cells can be discerned. We confirm in detail an earlier report of the presence in the same deposits of tabulates, an extinct crown group anthozoan form. Other sections reveal structures that most closely resemble sections of basal modern corals. A large number of fossils similar to modern hydrozoan gastrulae were also observed. These again displayed great morphological consistency. Though only a single example is available, a microscopic animal remarkably similar to a modern adult hydrozoan is also presented. Taken together, the new observations reported in this paper indicate the existence of a diverse and already differentiated cnidarian fauna, long before the Cambrian evolutionary event. It follows that at least stem group bilaterians must also have been present at this time.
journal_name
Dev Bioljournal_title
Developmental biologyauthors
Chen JY,Oliveri P,Gao F,Dornbos SQ,Li CW,Bottjer DJ,Davidson EHdoi
10.1006/dbio.2002.0714subject
Has Abstractpub_date
2002-08-01 00:00:00pages
182-96issue
1eissn
0012-1606issn
1095-564Xpii
S0012160602907141journal_volume
248pub_type
杂志文章abstract：:Spermatogonial stem cells are required for the initiation of spermatogenesis and the continuous production of sperm. In addition, they can acquire pluripotency and differentiate into derivatives of the three embryonic germ layers when cultured in the appropriate conditions. Therefore, understanding the signaling pathw...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2006.12.013
更新日期：2007-04-01 00:00:00
abstract：:We demonstrate that interspecific sequence conservation can provide a systematic guide to the identification of functional cis-regulatory elements within a large expanse of genomic DNA. The test was carried out on the otx gene of Strongylocentrotus purpuratus. This gene plays a major role in the gene regulatory networ...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.2002.0618
更新日期：2002-06-01 00:00:00
abstract：:During vesicular transport between the endoplasmic reticulum and the Golgi, members of the TMED/p24 protein family form hetero-oligomeric complexes that facilitate protein-cargo recognition as well as vesicle budding. In addition, they regulate each other's level of expression. Despite analyses of TMED/p24 protein dis...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2010.02.019
更新日期：2010-05-01 00:00:00
abstract：:In developing limb buds, Msx2 transcripts are expressed in the apical ectodermal ridge (AER) and in various regions of the limb mesenchyme. To identify DNA sequences responsible for Msx2 expression in the AER, we characterized the expression of LacZ reporter constructs driven by chicken Msx2 regulatory sequences in tr...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2004.03.005
更新日期：2004-06-15 00:00:00
abstract：:Oocyte maturation (meiosis reinitiation) in starfish is induced by the natural hormone 1-methyladenine (1-MeAde). Oocytes of Evasterias troschelii contain 0.43 pmole cyclic AMP/mg protein and 0.47 pmole cyclic GMP/mg protein. Upon stimulation by 1-MeAde the oocytes undergo a moderate (10-30%) decrease in their cAMP co...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(87)90166-7
更新日期：1987-06-01 00:00:00
abstract：:The Drosophila segment polarity gene known as shaggy or zeste white 3 encodes a ubiquitously expressed serine-threonine protein kinase which is critical for a number of important developmental processes. In the developing wing blade, clones of cells lacking the normal shaggy-zeste white 3 product form dense tufts of m...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1994.1081
更新日期：1994-03-01 00:00:00
abstract：:Pluripotent stem cells, termed embryonic germ (EG) cells, have been generated from both human and mouse primordial germ cells (PGCs). Like embryonic stem (ES) cells, EG cells have the potential to differentiate into all germ layer derivatives and may also be important for any future clinical applications. The developm...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2007.11.007
更新日期：2008-01-15 00:00:00
abstract：:Vascular smooth muscle of the head derives from neural crest, but developmental mechanisms and early transcriptional drivers of the vSMC lineage are not well characterized. We find that in early development, the transcription factor foxc1b is expressed in mesenchymal cells that associate with the vascular endothelium....
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2019.06.005
更新日期：2019-09-01 00:00:00
abstract：:Antibodies to nonerythroid alpha spectrin (p 230) were used to study the distribution of this polypeptide in mouse germ cells, zygote, and early embryonic cells. In the primordial germ cells, fetal oocytes, and spermatogonia, spectrin was found predominantly in the form of a narrow condensed subplasmalemmal band, as i...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(86)90389-1
更新日期：1986-03-01 00:00:00
abstract：:Projection neurons of the developing cerebral cortex are generated in the cerebral ventricular zone and subsequently move to the developing cortical plate via radial migration. Conversely, most inhibitory interneurons originate in the ganglionic eminences and enter the developing cortical plate by tangential migration...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2006.06.040
更新日期：2006-10-01 00:00:00
abstract：:The myelin of the peripheral nervous system from the shiverer mutant mice is characterized by the absence of myelin basic protein, while the other myelin protein components are present at normal levels. Myelin lamella formation is normal in the shiverer mutant. Therefore, by using antiserum against myelin basic protei...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(84)90277-x
更新日期：1984-09-01 00:00:00
abstract：:Gene network analysis requires computationally based models which represent the functional architecture of regulatory interactions, and which provide directly testable predictions. The type of model that is useful is constrained by the particular features of developmentally active cis-regulatory systems. These systems...
journal_title：Developmental biology
pub_type： 杂志文章,评审
doi：10.1006/dbio.2002.0617
更新日期：2002-06-01 00:00:00
abstract：:We determined expression and function of a cell membrane protein in the developing chick retinotectal system identified by a monoclonal antibody (mAb 4H5) and the corresponding antiserum. Our data revealed that the protein shares a series of properties, including the N-terminal amino acid sequence, with a cell adhesio...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1994.1284
更新日期：1994-10-01 00:00:00
abstract：:We have investigated the accumulation and adenylation of the maternal mRNA during oogenesis in the oocytes of the marine worm Urechis caupo. The analysis, using in vitro translation and cDNA probes to assay for specific mRNAs, demonstrates that different maternal mRNAs accumulate with different patterns during oogenes...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(86)90347-7
更新日期：1986-09-01 00:00:00
abstract：:In mammalian fertilization, paternal chromatin is exhaustively remodeled, yet the maternal contribution to this process is unknown. To address this, we prevented the induction of meiotic exit by spermatozoa and examined sperm chromatin remodeling in metaphase II (mII) oocytes. Methylation of paternal H3-K4 and H3-K9 r...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2006.08.006
更新日期：2007-01-15 00:00:00
abstract：:Early mammalian embryogenesis is controlled by mechanisms governing the balance between pluripotency and differentiation. The expression of early lineage-specific genes can vary significantly between species, with implications for developmental control and stem cell derivation. However, the mechanisms involved in patt...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2012.12.008
更新日期：2013-03-01 00:00:00
abstract：:The chicken retina is capable of limited regeneration. In response to injury, some Müller glia proliferate and de-differentiate into progenitor cells. However, most of these progenitors fail to differentiate into neurons. The Notch pathway is upregulated during retinal regeneration in both fish and amphibians. Since t...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2007.09.046
更新日期：2007-12-01 00:00:00
abstract：:The eukaryotic initiation translation factor eIF6 is a highly conserved, essential protein implicated in translation. eIF6 is regulated in vivo by extracellular signals, such as IGF signaling (for a review see Miluzio et al., 2009). In Xenopus, eif6 over-expression causes a delay in eye development (De Marco et al., 2...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2017.04.017
更新日期：2017-07-01 00:00:00
abstract：:Primary cultures of cardiac myocytes from newborn normal and genetically cardiomyopathic (strain UM-X7.1) hamsters were analyzed by electron microscopy and immunofluorescent staining for myosin, actin, tropomyosin, and alpha-actinin. Antibody staining of these contractile proteins demonstrates that both normal and car...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(83)90091-x
更新日期：1983-06-01 00:00:00
abstract：:The relationship between cellular position and growth control has been studied in cultures of dissociated fragments of mouse limb bud cells. Using cells derived from various positions along the anterior-posterior axis of the limb bud we have developed culture conditions that optimize growth of positionally isolated ce...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(92)90208-x
更新日期：1992-05-01 00:00:00
abstract：:The outstanding migration and differentiation capacities of neural crest cells (NCCs) have fascinated scientists since Wilhelm His described this cell population in 1868. Today, after intense research using vertebrate model organisms, we have gained considerable knowledge regarding the origin, migration and differenti...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2010.05.012
更新日期：2010-08-15 00:00:00
abstract：:Migration of Anterior Visceral Endoderm (AVE) is a critical symmetry breaking event in the early post-implantation embryo development and is essential for establishing the correct body plan. Despite much effort, cellular and molecular events influencing AVE migration are only partially understood. Here, using time-lap...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2019.03.016
更新日期：2019-06-15 00:00:00
abstract：:The sea urchin sperm receptor isolated from the eggs of Strongylocentrotus purpuratus is a high molecular weight proteoglycan-like molecule. Previous studies in our laboratory suggested that the sperm receptor has two functional components, glycosaminoglycan chains that are responsible for sperm binding and polypeptid...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(86)90088-6
更新日期：1986-11-01 00:00:00
abstract：:FoxC, FoxF, FoxL1 and FoxQ1 genes have been shown to be clustered in some animal genomes, with mesendodermal expression hypothesised as a selective force maintaining cluster integrity. Hypotheses are, however, constrained by a lack of data from the Lophotrochozoa. Here we characterise members of the FoxC, FoxF, FoxL1 ...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2010.01.015
更新日期：2010-04-15 00:00:00
abstract：:Sex in the nematode Caenorhabditis elegans is normally determined by the X chromosome to autosome (X:A) ratio, with XX hermaphrodites and XO males. Previous work has shown that a set of at least four autosomal genes (her-1, tra-2, tra-3, and tra-1) is signaled by the X:A ratio and appears to act in a regulatory pathwa...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(84)90077-0
更新日期：1984-11-01 00:00:00
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journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.2001.0442
更新日期：2001-11-15 00:00:00
abstract：:Mouse embryo limb cells carrying either the brachypodism (bpH/bpH) mutation or its wild-type (+/+) allele were tested for their ability to accumulate cyclic AMP in response to prostaglandin E2 (PGE2) between Embryonic Days E12 and E14. Mutant cells exhibited a precocious increase in cyclic AMP. In the absence of PGE2 ...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(90)90372-p
更新日期：1990-12-01 00:00:00
abstract：:Most, if not all, endocrine cells seem capable of synthesizing and storing more than one hormone. Such cellular colocalization of hormones can be due either to the presence of two or more specific granules within the cells or to colocalization of the hormones within a single granule. The present study was performed to...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(92)90122-w
更新日期：1992-10-01 00:00:00
abstract：:Using optical imaging assays, we investigated the dynamics of acetylcholine receptors (AChRs) at laminin-associated clusters on cultured myotubes in the absence or presence of the nerve-derived clustering factor, agrin. Using fluorescence recovery after photobleaching (FRAP) on fluorescent bungarotoxin-labeled recepto...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2005.09.041
更新日期：2005-12-01 00:00:00
abstract：:Regulation of peptide neurotransmitter metabolism was examined in dissociated cell cultures of neonatal rat sympathetic and sensory ganglia. Previous studies have shown that pineal gland conditioned medium (PCM) influences substance P (SP) and somatostatin (SS) metabolism in sympathetic neurons in vitro. The present s...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(84)90061-7
更新日期：1984-11-01 00:00:00
