CST Guide:

Section I: Research Areas
chapter 06: Development and differentiation
GATA-6, a zinc finger
protein that regulates
endoderm development,
is expressed in colon
carcinoma (KM12) but
not ovarian carcinoma
(SK-OV-3) cells.
Events
Sox2 (Alexa Fluor ® 647 Conjugate)
Pluripotency marker Sox2 is expressed
in embryonic carcinoma NTERA-2 cells.
Sox2 (D6D9) XP ® Rabbit mAb (Alexa Fluor ® 647 Conjugate) #5067:
Flow cytometric analysis of HeLa cells (blue) and NTERA-2 cells (green)
using #5067.
While much of modern stem cell research has focused on the isolation or generation of pluripotent
stem cells, more recent efforts have been directed towards understanding and exploiting the process
of transdifferentiation, or direct reprogramming. Transdifferentiation describes a process whereby a
terminally differentiated cell is converted into a functionally distinct cell type, without first proceeding
through a pluripotent phase of development. Transdifferentiation is considered a promising avenue
of exploration in regenerative medicine, as transdifferentiated cells could provide for direct in situ
replacement of damaged cells without the need for in vitro differentiation, as required by iPSCs. Transdifferentiation
can be experimentally induced by the forced expression of a combination of transcription
factors, unique for each cell type. For example, mouse cardiac fibroblasts can be transdifferentiated
into cardiomyocytes by forced expression of GATA-4, MEF2C, and Tbx5 (Qian, L. et al. (2012) Nature
485, 593–598.).
Miwi is expressed in
mouse testes and is a
marker for germ cells.
Several additional transcription factor families regulate differentiation along lineage-specific pathways.
These include members of the zinc finger, homeobox, forkhead box (Fox), helix-loop-helix (bHLH), T
box, Paired box (Pax), and Sox protein families. Members within each group are classified by the presence
of unique DNA binding domains, which bind to specific promoter regions to regulate expression
of genes necessary for each stage of development. One example are the GATA proteins, an extremely
large, highly conserved family of zinc finger proteins, the members of which play diverse and critically
important roles throughout development. Similarly, homeobox transcription factors, the product of Hox
genes, contain a helix-turn-helix homeodomain and are critical for regulating the transcription of genes
that specify development along the anterior-posterior body axis.
Germ cell marker DDX4 is expressed in mouse testes but not mouse brain.
DDX4 (D10C5) Rabbit mAb #8761:
Confocal IF analysis of mouse testes
(left) and mouse brain (right) using
#8761 (green). Actin filaments were
labeled with DY-554 phalloidin (red).
Blue pseudocolor = DRAQ5 ® #4084
(fluorescent DNA dye).
Miwi (D92B7) XP ® Rabbit mAb #6915:
Confocal IF analysis of mouse testes
using #6915 (green). Actin filaments
were labeled with DY-554 phalloidin (red).
Blue pseudocolor = DRAQ5 ® #4084
(fluorescent DNA dye).
GATA-6 (D61E4) XP ® Rabbit mAb
#5851: Confocal IF analysis of KM12 (top)
and SK-OV-3 (bottom) cells using #5851
(green). Actin filaments were labeled with
DY-554 phalloidin (red).
Stem Cell Differentiation and Transdifferentiation
Pluripotent stem/progenitor cells, including ESCs and iPSCs, can be induced to develop into lineagespecific
progenitor cells, representing each of the three primary germ layers established during
gastrulation: ectoderm, mesoderm, and endoderm. Further differentiation then proceeds progressively
along the respective lineage-specific pathways, culminating in terminal differentiation and yielding a
cell with a lineage-specific functional phenotype. Cells that have differentiated into a specific lineage
may be identified using lineage markers—antigens with a spatially or temporally restricted pattern of
expression that can be used to identify cells within specific lineage pathways.
Neurofilament-L (C28E10) Rabbit
mAb #2837 and β3-Tubulin (TU-20)
Mouse mAb #4466: Confocal IF
analysis of neuroepithelial clusters
differentiated from human iPS cells,
showing multiple neurite extensions,
using #2837 (red) and #4466 (green).
Blue pseudocolor = DRAQ5 ® #4084
(fluorescent DNA dye).
Neurofilament-L
and β3-Tubulin
are markers for
neuronal cells and
antibodies for these
proteins label cells
in neuroepithelial
clusters.
Induced Pluripotency (iPS)
Embryonic Stem Cell
Primordial Germ Cell
Ectoderm
Mesoderm
Endoderm
Development and Differentiation Signaling
Development along each lineage is regulated by several signaling pathways that control cell division,
growth, and differentiation, including BMP/TGF-β, Notch, Wnt/β-catenin, Hedgehog, and Hippo pathways.
Each of these pathways is regulated by a complex array of genetic, epigenetic, and exogenous
signaling factors that serve to guide cell fate and behavior during development and differentiation.
Additional details of signaling nodes within each of these pathways can be found in the pathway
diagrams to follow.
β-catenin is
abundantly expressed
in the mammalian gut,
where it regulates
epithelial cell adhesion.
Neural Stem Cell
Mesenchymal
Stem Cell
Neural Crest Glial
Neuron
Adipocyte, Hematopoietic Hepatocyle Pancreatic Cell
Progenitor Progenitor Myocyte, Osteocyte Stem Cell
Astrocyte Oligodendrocyte Neuron
Hemangioblast
© 2002–2015 Cell Signaling Technology, Inc.
Endodermal
Progenitor
Wnt/β-catenin Signaling
The widely conserved Wnt/β-Catenin pathway regulates stem cell pluripotency and cell fate decisions
during development. Wnt signaling is triggered by binding of the Wnt ligand to Frizzled receptors in
complex with the co-receptor LRP5/6, initiating a signaling cascade that results in stabilization and
nuclear translocation of the transcriptional co-regulator, β-catenin. Nuclear β-catenin functions as a
transcriptional co-activator, promoting the transcription of genes that regulate proliferation and differentiation.
β-catenin also plays a highly important role in the planar-cell-polarity pathway, regulating
cell-cell contact via adherens junctions.
β-Catenin (D10A8) XP ® Rabbit mAb
#8480: Confocal IF analysis of mouse
colon using #8480 (green). Actin filaments
were labeled with DY-554 phalloidin (red).
Blue pseudocolor = DRAQ5 ® #4084
(fluorescent DNA dye).
154 For Research Use Only. Not For Use in Diagnostic Procedures. See pages 302 & 303 for Pathway Diagrams, Application, and Reactivity keys.
www.cellsignal.com/cstdevelopment 155