developmental genes screening - (Feb/05/2007 )
Guys I am new to genetics forum, I as an undergrad started to work in a genetics lab recently-my first assignment my boss gave was to come up with ideas to do a genetic screen to identify genes involved involved in development (most of them will be lethal and so how will you overcome this pblm)--in flies
pls help me out
Thanks in advance
Hi drosophilastarter,
One possible approach is Morpholino antisense. This is the standard tool for gene knockdown in zebrafish labs, and it works in flies; see the figure by Nipam Patel in:
Ekker SC, Larson JD. Morphant technology in model developmental systems. Genesis. 2001 Jul;30(3):89-93. Figure 3 panel a-d.
This is available online:
http://www3.interscience.wiley.com/cgi-bin...006234/PDFSTART
Morpholinos are steric-blocking antisense that can be used at low doses to partially inhibit gene expression, useful to observe effects of a gene for which a knockout would be embryonic lethal. For a description see Wikipedia: Morpholinos which is accessible from this link:
http://en.wikipedia.org/wiki/Morpholino
For more information about Morpholinos see the Gene Tools website, www.gene-tools.com.
Morpholinos have not caught on in flies, but some recent work has been published:
Pilot F, Philippe JM, Lemmers C, Lecuit T. Spatial control of actin organization at adherens junctions by a synaptotagmin-like protein Btsz. Nature. 2006 Aug 3;442(7102):580-4. Epub 2006 Jul 9.
For a database of publications related to Morpholino oligos, see pubs.gene-tools.com
Using a Morpholino to knockdown a gene is much easier and faster than constructing a knockout. A Morpholino does not modulate the expression of hundreds of off-target genes. This off-target expression modulation is a known disadvantage of siRNA:
Short interfering RNAs can induce unexpected and divergent changes in the levels of untargeted proteins in mammalian cells. Scacheri PC, Rozenblatt-Rosen O, Caplen NJ, Wolfsberg TG, Umayam L, Lee JC, Hughes CM, Shanmugam KS, Bhattacharjee A, Meyerson M, Collins FS. Proc Natl Acad Sci U S A. 2004 Feb 17;101(7):1892-7. Epub 2004 Feb 09.
For screening, reduced prices are available for sets of 100 oligos.
Best regards,
- Jon
wow, what a cool technique, Thanks Jon that was lot helpful, I am reading on it and I will use it in my next lab meeting, I will somehow persuade my boss and try this.
Thanks again Jon