Abstract：
:There has been a resurgence of interest in comparative embryology. It is now important to be able to compare gene expression in different species at similar developmental stages. One phenomenon which may make it difficult to compare embryos in this way is heterochrony--a change in developmental timing during evolution. It is not clear whether heterochrony can affect the intermediate stages of embryonic development, when many important genes involved in pattern formation are expressed. A prevalent view is that these so-called phylotypic stages are resistant to evolutionary change because they are when the body plan is laid down. Haeckel's famous drawings, which show different vertebrates developing from virtually identical somite-stage embryos, are still used to support this idea. I have reexamined the morphological data relating to developmental timing in somite-stage embryos. The data reveal striking patterns of heterochrony during vertebrate evolution. These shifts in developmental timing have strongly affected the phylotypic stage, which is therefore poorly conserved and is more appropriately described as the phylotypic period. This is contrary to the impression created by Haeckel's drawings, which I show to be inaccurate and misleading. The study of gene expression in embryos which show heterochrony could give important insights into evolutionary and developmental mechanisms.
journal_name
Dev Bioljournal_title
Developmental biologyauthors
Richardson MKdoi
10.1006/dbio.1995.8041subject
Has Abstractpub_date
1995-12-01 00:00:00pages
412-21issue
2eissn
0012-1606issn
1095-564Xpii
S0012-1606(85)78041-4journal_volume
172pub_type
杂志文章,评审abstract：:To investigate the spatiotemporal dynamics of skin pattern formation, we developed a simple method for artificially disarranging the placement of all three pigment cell types in the body trunk of zebrafish (Danio rerio). We generated transgenic fish with melanophores that ectopically expressed a variant of channelrhod...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2018.12.019
更新日期：2020-04-01 00:00:00
abstract：:Amphibian embryos from the genus Xenopus are among the best species for understanding early vertebrate development and for studying basic cell biological processes. Xenopus, and in particular the diploid Xenopus tropicalis, is also ideal for functional genomics. Understanding the behavior of genes in this accessible m...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2004.04.023
更新日期：2004-07-15 00:00:00
abstract：:Initiation of the development of the anterior-posterior axis in the mouse embryo has been thought to take place only when the anterior visceral endoderm (AVE) emerges and starts its asymmetric migration. However, expression of Lefty1, a marker of the AVE, was recently found to initiate before embryo implantation. This...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2007.06.020
更新日期：2007-09-01 00:00:00
abstract：:The spe-9 gene is required for fertility in Caenorhabditis elegans and encodes a sperm transmembrane protein with an extracellular domain (ECD) that contains 10 epidermal growth factor (EGF) repeats. Deletion analysis reveals that the EGF repeats and the transmembrane domain are required for fertilization. In contrast...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2004.05.014
更新日期：2004-08-15 00:00:00
abstract：:Wnt signaling pathways have been demonstrated to play important roles in controlling tissue patterning and cell proliferation. In the gastrointestinal tract, mutations that lead to activation of the canonical Wnt pathway through beta-catenin result in familial and sporadic colon cancers. The downstream transcription f...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/s0012-1606(03)00185-4
更新日期：2003-07-15 00:00:00
abstract：:During its development the epidermis of the pf/pf mutant mouse is invaded by cells from the underlying dermis. These invading cells establish a network of cells including fibroblasts, endothelial cells, and nerve fibers, throughout the epidermis. Subsequent to these events the keratohyalin protein, filaggrin, is drast...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(84)90194-5
更新日期：1984-04-01 00:00:00
abstract：:We have cloned a Caenorhabditis elegans homologue of the Drosophila gap gene hunchback (hb) and have designated it hbl-1 (hunchback-like). hbl-1 encodes a predicted 982-amino-acid protein, containing two putative zinc-finger domains similar to those of Drosophila Hunchback. The gene is transcribed embryonically, but u...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1998.9096
更新日期：1999-01-15 00:00:00
abstract：:The differentiation of three anterior pituitary cell types is regulated by the tissue-specific POU domain factor Pit-1, which is initially expressed on Embryonic Day 13.5-14 in mice. The Pit-1 gene remains continuously, highly expressed in the somatotrope, thyrotrope, and lactotrope cells of the adult. Using the Pit-1...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1996.8472
更新日期：1997-02-01 00:00:00
abstract：:Drosophila Polycomb Repressive Complex 2 (PRC2) is a lysine methyltransferase that trimethylates histone H3 lysine 27 (H3K27me3), a modification essential for Polycomb silencing. Mutations in its catalytic subunit, E(Z), that abolish its methyltransferase activity disrupt Polycomb silencing, causing derepression of Po...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2011.12.007
更新日期：2012-04-15 00:00:00
abstract：:Sensory perception of light is mediated by specialized Photoreceptor neurons (PRs) in the eye. During development all PRs are genetically determined to express a specific Rhodopsin (Rh) gene and genes mediating a functional phototransduction pathway. While the genetic and molecular mechanisms of PR development is well...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2015.12.026
更新日期：2016-02-15 00:00:00
abstract：:Normal growth and morphogenesis of the cranial vault reflect a balance between cell proliferation in the sutures and osteogenesis at the margins of the cranial bones. In the clinical condition craniosynostosis, the sutures fuse prematurely as a result of precocious osteogenic differentiation and craniofacial malformat...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.2001.0533
更新日期：2002-03-01 00:00:00
abstract：:Cerebellum development involves the coordinated production of multiple neuronal cell types. The cerebellar primordium contains two germinative zones, the rhombic lip (RL) and the ventricular zone (VZ), which generate different types of glutamatergic and GABAergic neurons, respectively. What regulates the specification...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2012.02.017
更新日期：2012-05-01 00:00:00
abstract：:All metazoan genomes encode multiple RAS GTPase activating proteins (RasGAPs) that negatively regulate the conserved RAS/MAPK signaling pathway. In mammals, several RasGAPs exhibit tumor suppressor activity by preventing excess RAS signal transduction. We have identified gap-3 as the to date missing Caenorhabditiseleg...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2008.08.026
更新日期：2008-11-15 00:00:00
abstract：:Mammalian CYPHER (Oracle, KIA0613), a member of the PDZ-LIM family of proteins (Enigma/LMP-1, ENH, ZASP/Cypher, RIL, ALP, and CLP-36), has been associated with cardiac and muscular myopathies. Targeted deletion of Cypher in mice is neonatal lethal possibly caused by myopathies. To further investigate the role of cyphe...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2006.07.032
更新日期：2006-11-15 00:00:00
abstract：:Voltage-gated Na(+) and K(+) channels are localized to distinct subcellular domains in mammalian myelinated nerve fibers. Specifically, Na(+) channels are clustered in high densities at nodes of Ranvier, while K(+) channels are found in juxtaparanodal zones just beyond regions of axoglial contact where sequential laye...
journal_title：Developmental biology
pub_type： 杂志文章,评审
doi：10.1006/dbio.2001.0326
更新日期：2001-08-01 00:00:00
abstract：:The Hedgehog (Hh) and Notch signal transduction pathways control a variety of developmental processes including cell fate choice, differentiation, proliferation, patterning and boundary formation. Because many components of these pathways are conserved, it was predicted and confirmed that pathway components are largel...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2006.08.064
更新日期：2006-12-01 00:00:00
abstract：:Receptor protein tyrosine phosphatases (RPTPs) have been shown to play key roles in regulating axon guidance and synaptogenesis. HmLAR2, one of two closely related LAR-like RPTPs in the embryonic leech, is expressed in a few central neurons and in a unique segmentally-iterated peripheral cell, the comb cell (CC). Here...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2008.05.522
更新日期：2008-08-01 00:00:00
abstract：:Cadherin-mediated cell-cell interactions are thought to be critical in controlling cell sorting during embryogenesis. Here, we report that chimeric embryos generated with N-cadherin-deficient (N-cadherin(-/-)) embryonic stem cells develop further than embryos completely lacking N-cadherin only when the myocardium cons...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.2001.0250
更新日期：2001-06-01 00:00:00
abstract：:The MEI-1/MEI-2 microtubule-severing complex, katanin, is required for oocyte meiotic spindle formation and function in C. elegans, but the microtubule-severing activity must be quickly downregulated so that it does not interfere with formation of the first mitotic spindle. Post-meiotic MEI-1 inactivation is accomplis...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2009.04.004
更新日期：2009-06-15 00:00:00
abstract：:An organism's genome sequence serves as a blueprint for the proteins and regulatory RNAs essential for cellular function. The genome also harbors cis-acting non-coding sequences that control gene expression and are essential to coordinate regulatory programs during embryonic development. However, the genome sequence i...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2011.03.007
更新日期：2011-09-15 00:00:00
abstract：:Ca2+-sensitive microelectrodes were used to study changes in cytoplasmic free calcium during progesterone-induced meiotic maturation in Xenopus laevis oocytes. In contrast to previous reports, no changes were detected during the maturation process, although a large activation pulse of Ca2+ was seen when in vitro matur...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/0012-1606(85)90475-0
更新日期：1985-06-01 00:00:00
abstract：:This study evaluated Na/K-ATPase alpha 1- and alpha 3-subunit isoform polypeptide expression and localization during bovine preattachment development. Na/K-ATPase cation transport activity from the one-cell to blastocyst stage was also determined by measuring ouabain-sensitive 86Rb+ uptake. Both alpha1- and alpha 3-su...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1998.8874
更新日期：1998-05-01 00:00:00
abstract：:Malpighian tubules are the osmoregulatory and detoxifying organs of Drosophila and its proper development is critical for the survival of the organism. They are made up of two major cell types, the ectodermal principal cells and mesodermal stellate cells. The principal and stellate cells are structurally and physiolog...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2014.11.003
更新日期：2015-02-15 00:00:00
abstract：:We have cloned a member of the fork head/HNF-3 family of transcription factors from the nematode Caenorhabditis elegans. Within the predicted DNA binding domain, this gene, called Ce-fkh-1, is 75-78% identical to the Drosophila fork head and rat liver HNF-3 alpha, beta, and gamma genes. Ce-fkh-1 mRNA is highly enriche...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1006/dbio.1996.0219
更新日期：1996-09-15 00:00:00
abstract：:The vertebrate cranial base is a complex structure composed of bone, cartilage and other connective tissues underlying the brain; it is intimately connected with development of the face and cranial vault. Despite its central importance in craniofacial development, morphogenesis and tissue origins of the cranial base h...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2008.07.016
更新日期：2008-10-01 00:00:00
abstract：:The Xenopus helix-loop-helix transcription factor Hairy2 is essential for neural crest progenitor survival and maintains cells in a mitotic undifferentiated pre-neural crest state. However, its mode of action remains largely unknown. Here we show that a Hairy2 DNA-binding mutant is unable to promote cell survival and ...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2008.07.026
更新日期：2008-10-15 00:00:00
abstract：:In many non-mammalian vertebrates, adult dentitions result from cyclical rounds of tooth regeneration wherein simple unicuspid teeth are replaced by more complex forms. Therefore and by contrast to mammalian models, the numerical majority of vertebrate teeth develop shape during the process of replacement. Here, we ex...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2013.02.007
更新日期：2013-05-15 00:00:00
abstract：:The homeobox gene sine oculis (so) is required for the development of the entire visual system in Drosophila, which includes the compound eyes, the ocelli, the optic lobe of the brain and the Bolwig's organ. During ocelli development, so expression labels, together with eyes absent (eya), the emergence of the ocellar ...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2010.05.494
更新日期：2010-08-15 00:00:00
abstract：:Thyroid hormone deficiency is known to deeply affect cerebellum post-natal development. We present here a detailed analysis of the phenotype of a recently generated mouse model, expressing a dominant-negative TRα1 mutation. Although hormonal level is not affected, the cerebellum of these mice displays profound alterat...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/j.ydbio.2011.05.657
更新日期：2011-08-15 00:00:00
abstract：:Single cells from 512-cell Xenopus embryos, totally labeled with intracellular horseradish peroxidase, were transplanted orthotopically (from either dorsal or lateral marginal zone) or heterotopically (between these two marginal zones) to unlabeled host embryos at the 512-cell stage. At tailbud stage 23 the locations,...
journal_title：Developmental biology
pub_type： 杂志文章
doi：10.1016/s0012-1606(89)80043-0
更新日期：1989-01-01 00:00:00
