Table of Contents
How does the GAL4 UAS system work?
The Gal4/UAS system Gal4 is a transcriptional activator that binds to UAS enhancer sequences found in DNA. It then recruits transcription machinery to the site to induce gene expression. You can quickly mate your UAS-YFG line with a variety of Gal4 lines and study gene expression in many different tissue types!
What is the effect of GAL4 on UAS?
The presence of GAL4, by itself, in these cells has little or no effect, since GAL4’s main effect is to bind to a UAS region, and most cells have no (or innocuous) UAS regions. Since Gal4 by itself is not visible, and has little effect on cells, the other necessary part of this system are the “reporter lines”.
How does GAL4 activate transcription?
This protein represents a large fungal family of transcription factors, Gal4 family, which includes over 50 members in the yeast Saccharomyces cerevisiae e.g. Oaf1, Pip2, Pdr1, Pdr3, Leu3. Gal4 recognizes genes with UASG, an upstream activating sequence, and activates them.
What is the Yeast GAL system and explain the significance of UAS and GAL4?
The GAL4/upstream activating sequence (UAS) system is one of the most powerful tools for targeted gene expression. It is based on the properties of the yeast GAL4 transcription factor which activates transcription of its target genes by binding to UAS cis-regulatory sites.
What chromosome is Gal4 on?
| Line | Gene | Chr. |
|---|---|---|
| Line | Gene | Chr. |
| CR00323 | Marf | X |
| CR00446 | Dsor1 | X |
Is Gal4 an activator?
Yeast Gal4, one of the first known acidic activators, is responsible for the regulation of genes involved in galactose catabolism (41). In the absence of galactose, Gal4 is inhibited by the repressor Gal80.
Does Gal4 bind to galactose?
Interestingly, however, this effect only occurs when the cells are grown in the presence of glycerol as the main carbon source. By contrast however, in the presence of glucose, GAL4 does not bind to DNA and the addition of galactose has no effect.
Does GAL4 bind to galactose?
What chromosome is GAL4 on?
What does Gal4 bind to to initiate transcription?
In Mediator, Gal4 binds to the Srb10 and Gal11 subunits, binding Gal11 in two separate regions. Other acidic activators such as yeast Gcn4 have also been found to interact with numerous polypeptides in vitro (6, 15, 35).
Does Gal4 bind to DNA?
What is the function of the Gal4 UAS system?
GAL4/UAS is a binary system with two main components: The yeast transcription factor GAL4 (expressed in a tissue and/or time-specific pattern) activates transgenes under the control of a UAS (upstream activating sequence) promoter, thus enabling spatiotemporal specific transgene expression.
Can GAL4-UAS detect fusion protein overexpression?
The GAL4-UAS system can produce levels of fusion proteins that exceed those of endogenous proteins by several orders of magnitude. To identify potential artifacts that are caused by fusion protein overexpression, it is essential to compare the characteristics of the ectopically expressed fusion proteins with those of their endogenous counterparts.
What is the biological activity of GAL4?
In most cases, GAL4 has no biological activity in insect cells, although in some cases, such as high-level expression in the retina, using GMR-GAL4, may cause mild artifactual phenotypes, possibly due to aggregation of the GAL4 at high concentrations.
What is the role of GAL4 in transgenic protein expression?
The transgene of interest is placed downstream of a GAL4 upstream activating sequence that supports transcription of the construct only in the presence of GAL4. In this way, the pattern of transgenic protein expression can be tailored, according to the driver line used, to the requirements of the investigator.