Fishman, in particular, wanted to advance his studies in oncodevelopmental biology, exploiting proteins involved in
embryonic development as tumor markers.
Perhaps the most astonishing stage of pregnancy is that of
the embryonic development as your unborn child goes from being the size of a sesame seed and looking like a tadpole to being the size of a kidney bean with some neck definition and tiny webbed fingers and toes.
Not exact matches
As specialized cells are generated during
embryonic development, they are programmed to use only a limited amount of the total genetic information present in the nucleus to produce the proteins required for their particular function.
Embryonic stem cells are produced during
development by the same process of epigenetic programming that later will produce adult cells such
as skin and brain.
This process of restricting the use of genetic information during
embryonic development is known
as epigenetic programming» programming that is not part of the DNA code itself but imposed on that code during
embryonic development.
This complex society may be said to begin with conception, or with a late stage of
embryonic development, or with early childhood, depending upon the purpose which determines what one takes
as its defining characteristic.
«Thus, we hypothesize that Gdf3 combines with Ndr1 and Ndr2 to facilitate Nodal signaling during zebrafish
development, acting
as an essential factor in
embryonic patterning,» said Pelliccia, a graduate student in molecular biology.
Animals such
as salamanders and planaria regenerate tissues by rekindling genetic mechanisms that guide the patterning of body structures during
embryonic development.
It was all sequentially programmed,
as if the creator booted up the cosmos at creation and let it run, or,
as Robert Chambers put it when talking about
embryonic development, «like Mr Babbage programming his Engine».
How do you visualise the extremely small forces connected to processes in our body, such
as embryonic growth and
development?
When Kaufman, Zon and colleagues looked to see what was different about these early cancer cells, they found that crestin and the other activated genes are the same ones turned on during zebrafish
embryonic development — specifically, in the stem cells that give rise to the pigment cells known
as melanocytes, within a structure called the neural crest.
Manuel Eguren has analysed the biological consequences of Cdh1 elimination in rapidly dividing cells,
as part of his doctoral research project in Malumbres's group; he focused on progenitors from the nervous system during
embryonic development in mice.
Salk scientists and colleagues have proposed new molecular criteria for judging just how close any line of laboratory - generated stem cells comes to mimicking
embryonic cells seen in the very earliest stages of human
development, known
as naïve stem cells.
Cell migration is highly coordinated and occurs in processes such
as embryonic development, wound healing, the formation of new blood vessels, and tumour cell invasion.
The zebrafish is used
as a model organism for research into the
embryonic development of vertebrates.
The ability of a fertilized egg to generate both
embryonic and extra-
embryonic tissues is referred to
as «totipotency,» an ultimate stem cell state seen only during the earliest stages of
embryonic development.
Animals
as varied
as grasshoppers and mice build their bodies by assembling repetitive pieces during
embryonic development.
In addition, researchers found that the gene families related to whale's body hair and sensory receptors were contracted, such
as Keratin - related gene families associated with hair formation, several Hox genes that play an important role in the body plan and
embryonic development.
The next step, he says, is to investigate how
embryonic mouse brains with induced folds develop
as they mature past the fetal stages of
development and to look across species to see if the gene has similar effects in other mammals.
As described in the journal Genes &
Development, the researchers identified a new pathway controlling heterochromatin organisation in mouse
embryonic stem cells.
Other potential uses of
embryonic stem cells include investigation of early human
development, study of genetic disease and
as in vitro systems for toxicology testing.
However, malformation of skeletal bones during embryogenesis also occurs in FOP patients and illustrates that the underlying genetic mutation occurs in a gene with functional importance in regulating chondro - osseous differentiation during
embryonic skeletal
development as well
as in adult musculoskeletal tissues.
Neural crest cells are a type of stem cell; during vertebrate
embryonic development, they eventually differentiate into specialized cells such
as those that make facial skeleton cells or those that create pigment cells.
«The ability to generate pure populations of these cell types is very important for any kind of clinically important regenerative medicine,» said Loh, «
as well
as to develop a basic road map of human
embryonic development.
In parallel, the roles of symmetric and asymmetric cell divisions are investigated
as a mechanism for governing stem cell self - renewal and differentiation during
embryonic development and in the adult.
The gene, known
as gata5, acts in
embryonic cells, which are primordial, unspecialized cells that form in the earliest stage of
embryonic development and are genetically programmed to evolve into one of many specialized cell types, such
as skeletal muscle cells, nerve cells, blood cells, skin cells, and liver cells.
The grand architecture of the human cortex, with its hundreds of distinct cell types, begins
as a uniform layer of neural stem cells and builds itself from the inside out during several months of
embryonic development.
They discovered that extra chromosome 21 - a genetic state known
as trisomy 21 - disturbs a key regulating gene called NRSF or REST, which in turn disturbs the cascade of other genes that control normal
development at the
embryonic stem cell stage.
Since the in vitro reprogramming systems are characterised by very low efficiency Petra's lab focuses on the systems where epigenetic reprogramming occurs naturally
as a part of normal
embryonic development.
«The current extension of induced pluripotency to human cells is a major
development and although it is early days for this technique it may well prove to be every bit
as signifcant
as the first derivation of human
embryonic stem cells nine years ago.
The telomeres are produced during
embryonic development but start to crumble away
as cells mature and divide.
As one example, using insights from
embryonic development, Jessell has been able to convert
embryonic stem cells into functioning motor neurons, facilitating the discovery of medicines to treat such diseases.
They found that groups of genes appear to work together in heart cells in a coordinated fashion — switching on and off
as a group at designated times during
embryonic development.
The research team hypothesized that HARs instead acted
as «enhancers,» controlling when and for how long certain genes were switched on during
embryonic development.
Integrating this new information into computational models, my colleagues and I predicted that about 5 percent of HARs function
as noncoding RNAs, while most are enhancers that control gene expression during
embryonic development.9
Thus, all research on lines of human
embryonic stem cells
as the cells of various phenotypes derived from these lines should aim to lexploration mechanisms or the
development and validation of therapeutic applicable to serious diseases.
The challenge takes on even more urgency with recent
developments, including a federal administration now more open to exploring the potential of stem cells, the recent FDA approval of a human trial involving
embryonic stem cells,
as well
as the reported case of a young boy who developed a brain tumor four years after receiving a stem - cell treatment for a rare genetic disorder.
These images show human
embryonic stem cell colonies,
as grown in 1998 by researchers at the University of Wisconsin — Madison, in different stages of
development.
We show that DONSON is expressed in progenitor cells of
embryonic human brain and other proliferating tissues, is co-expressed with components of the DNA replication machinery, and that Donson is essential for early
embryonic development in mice
as well, suggesting an essential conserved role for DONSON in the cell cycle.
For example, clusters containing genes that are upregulated during the course of ES cell differentiation (Table 3) include in order of time of expression: cluster 30 that represents genes which take part in the formation of the three
embryonic germ layers during gastrulation, i.e., Goosecoid, Cerberus like 1 homolog, Wnt3, Mesp1, Mixl1, mEomes and Even - skipped 1; cluster 15 containing molecular regulators of early mesoderm
development including Bmp2, Bmp5, Msx1, Msx2, Cripto, Tbx20, Hey2, Smad6, Vegfr2 (Kdr), Foxf1 and Hand1; cluster 20, which comprises regulatory and structural genes linked to hemopoiesis such
as Gata1, Nfe2, Klf1, Tie1, hemoglobins (Hba - x, Hbb - b1) and Glycophorin A; cluster 12, which is rich in genes involved in cardiac
development, e.g., Mef2c, Myl4, cardiac Troponin T2, Tropomodulin 1, myosin binding protein C, Bves, Angiopoietin 1 and Angiopoietin 2; and, cluster 4, which consists mostly of genes associated with neuronal
development and differentiation, for example, Neurog1, Neurog2, Olig2, Nkx6.1, Neurod4, Pou3f2, Pou3f4, Cacna2d3, Cacng4, Kcnq2 and EphA5.
Thus, the ability to measure DNAme in single cells has the potential to make important contributions to the understanding of several key biological processes, such
as embryonic development, disease progression and aging.
The study could provide clues to the genetic code that controls the expression of genes, and may also further our understanding of
embryonic development and diseases such
as cancer.
However, the disrupted
embryonic and fetal
development of cattle clones produced by SCNT has been used
as a model to elucidate the mechanisms of embryo loss, the maternal recognition of pregnancy (13, 14), and placental
development (15 ⇓ — 17).
Such work yields unique mechanistic insight by directly illustrating the complex spatial - temporal dynamics of fundamental cellular processes such
as mitosis, morphogenesis, polarization,
embryonic development, membrane trafficking and cytoskeleton dynamics.