The tag H3K27me3 (shown in green), can
switch gene activity off.
Not exact matches
Because the prion - forming protein identified in the study normally functions as a regulator of
gene activity, the researchers say their discovery raises the possibility that when it
switches to a prion state, it could alter genetic expression and bacterial behavior.
Because mice lacking both
genes would not be born alive, the scientists followed up this lead by making «conditional knockout mice,» in which Esrp1 and Esrp2
activity was normal early in fetal development, but then was
switched off in skin epithelial cells.
And the
switches can either increase or decrease the
activity of the
genes they regulate.
Within the duplicate regions, Carmona - Mora and her colleagues discovered many
switches, known as enhancers, important for controlling
activity of
genes.
Far from being junk, it's where molecular
switches that help control
gene activity are located.
Epigenetic «
switches» turn
gene activity up or down.
The
switches that control
gene activity are located here.
The pair of studies bring renewed focus to the epigenetics of T cells — the multilayered system of molecular
switches, accelerators, and throttles that controls the
activity of
genes.
«The movement of
genes within the nucleus, captured here using live imaging, seems to play a role in
switching their
activity on and off,» said first author Dr Stefanie Rosa from the John Innes Centre.
The researchers engineered a strain in which a Synechococcus
gene normally turned on during photosynthesis signals its
activity by
switching on the
gene for luciferase, an enzyme from another bacterium that drives a light - emitting chemical reaction.
The advances even point to strategies for exploiting these regulatory elements to treat disease, by
switching off disease
genes and turning up the
activity of healthy ones.
The project uncovered 4 million spots in our DNA that act as
switches controlling
gene activity.
The open portions of the genome include
genes themselves, as well as many regions that contribute to the regulation of their
activities (the
switches).
To start, the scientists examined previous experiments and identified several transcription factors — managerial proteins that
switch on the
activity of large sets of
genes — that seemed crucial to the ability of immature neurons to develop into adult sensory neurons.
DNA methylation is an epigenetic process in which small molecules — methyl groups - are added to
genes and fine - tune the
gene's
activity, like a dimmer
switch.
The alteration of
gene activity, called epigenetics, might result from modification of RNA molecules that interact with
genes; a modification of the packaging that carries DNA; molecular
switches attached directly to the DNA itself; or even something to do with the cell's power - stations, the mitochondria, Baugh said.
MYCN and its kin are «transcription factors,» proteins that bind to DNA and influence the rate at which genetic information is used by the cell — essentially serving as brightener / dimmer
switches for
gene activity.
They found three DNA deletions in the genetic
switch that controls the
activity of the Sonic hedgehog
gene.
Situated in front of the
gene, this
switch, called an enhancer, is a docking site for proteins that control the
gene's
activity.
Specifically, they analyzed the tumors» epigenome, an array of molecules that covers the surface of DNA and helps regulate
gene activity, acting like a control
switch to decide which
genes are active or inactive in the cell.
A mutation in a
switched - off
gene's
switch region might restore that
gene's
activity.
The researchers believe noise could play a role, so they combine single - molecule analysis with time - lapse movies of individual cells to track random
activity in many different
genes as the cells
switch states.
The operator is a segment of DNA that regulates the
activity of the structural
genes of the operon, somewhat like an on / off
switch.
Single - cell experiments show that
gene expression is random and «bursty,» Lin said, a feature that can emerge from slow
switching between promoter states with different
activities.
«Our study also highlights that growth of normal cells and cancer cells is driven by different
gene switches, suggesting that further work to find ways to control the
activity of such disease - specific
switches could lead to novel, highly specific approaches for therapeutic intervention», says Professor Jussi Taipale, who led the study.
Instead, most are
gene enhancers, which act like a dimmer
switch for a lightbulb, turning
gene activity up or down.
This confirmed that the
gene regulatory
switch is highly specific to one cell type, monocytes and that tumor cell invasion in the absence of this population had nothing to do with deregulated macrophage
activity.