Signal transduction involves the transmission and amplification of signals
from membrane, cytoplasmic, or nuclear receptors to the nucleus. Signaling
molecules include various hormones, growth factors, cytokines, chemokines,
neurotransmitters, extracellular matrix components, receptors, protein kinases,
protein phosphatases and DNA-binding proteins. The major purpose of signal
transduction is to incur changes in gene and protein expression as a result of
molecular stimuli or cellular changes. The simplest and most accurate technology
for analyze pathway expression is QIAGEN's PCR Arrays. See details here.
Different signaling pathways form an extremely complex system of
communication, which is the foundation of all cellular activities such as
morphogenesis, proliferation, development, differentiation, motility, invasion,
metastasis, and death. Signal transduction pathways involve protein-protein
interactions, making protein phosphorylation and dephosphorylation one of the
most crucial molecular switches. Protein phosphorylation represents a rather
transient signaling event, through which the signal finally goes into the
nucleus and leads to gene expression change. QIAGEN's PCR arrays allow
simultaneous mRNA expression analysis of a set of signaling pathway-focused
components, providing an accurate, fast, and easy overview of the relatively
long term and stable expression of the signal molecules.
It is worth mentioning that in vivo transcription does not occur on naked
DNA, but rather on nucleosome-condensed DNA (chromatin). Activation of
transcription requires an active remodeling of the chromatin structure at the
transcription start sites and within the transcribed regions. Therefore
chromatin structure plays an important role in transcription regulation. Please
use QIAGEN's Epigenetic Chromatin Modification Enzymes PCR array and
Epigenetic Chromatin Remodeling Factors PCR array to profile the expression of
the modification factors involved in this process.
Since the discovery of founding members of hundreds of signaling pathways,
new components continue to be identified. Many of these components were first
identified by quantitative genetic screenings such as microarrays or PCR arrays.
Other techniques such as overexpression, underexpression, animal-based mutant
phenotype assays, yeast two-hybrid, and coimmunoprecipitation assays were later
used to complete the current list of signaling components. There has been an
increasing appreciation for the contribution of the quantitative high or
semi-high through-put genetic studies.
How many intracellular signaling mechanisms does it take to mediate the
effects of 1000 receptors? With technological advances, our current views argue
that signaling pathways are being limited to a small number of canonical
components and that a large regulatory network actually has a graded effect on
signaling output. Since cellular processes are orchestrated by a much larger
network than previously thought, a much wider collection of genes that affect
previously well-defined canonical processes need to be studied. QIAGEN
gives researchers a great deal of flexibility by providing custom PCR arrays.
Customers can design their own PCR array gene content to suit their own research
needs. This has proven to be very successful and powerful especially with
pharmaceutical companies.
Given that quantitative genetic screenings measure points within the
signaling networks, a major challenge will be to construct the dynamic structure
of the networks in a particular research model at a particular time point.
QIAGEN has designed Pathway Central; GNC (Gene Network Central) and
GNCPro- a string of computational gene interaction analysis tools - to meet this
need.
After a PCR array study, functional RNAi screening of signaling networks
using quantitative cell-based assays can immediately follow. The RNAi screening
highlights the importance of individual components phenotypically within a
signaling network by depleting the protein expression. It also allows further
PCR array analysis of the effect of protein depletion on gene expression.
QIAGEN's Biology-on-Array fulfills this function by providing information
of both individual points and the overall picture. These powerful tools will
expedite uncovering cellular signaling physiology and pathology. Please see here
to learn more about Biology-on-Array.
Complete Array List
