"
Team:BrownTwo/Protocols/bbyeastchrom
From 2008.igem.org
| (3 intermediate revisions not shown) | |||
| Line 7: | Line 7: | ||
<p><br /> | <p><br /> | ||
<p>The Registry includes a growing number of parts for use in yeast, but there currently exist no BBa compatible yeast shuttle vectors. In our work, we have chosen to utilize Sikorski yeast vectors to integrate BBa parts into yeast chromosomes. [1] With genomic insertion, each transformation is stable, being reproduced with the rest of the chromosome. Additionally, exactly one copy of each insertion is present in transformed strains, allowing for precise control of the relative expression levels of multiple elements. The Sikorski vectors can be transformed into E. coli for construction and propagation. There exist four integrative vectors in the pRS30x family, each integrating at a different auxotrophic locus and containing the amino acid synthesis gene to fill that auxotrophy as a marker for integration. The vectors are not suitable for Biobrick construction- they each contain one extraneous Biobrick site, and lack the standard cloning site. Thankfully, there is a standard method for cloning BBa parts onto the pRS30x vectors for yeast chromosomal integration: [2] </p><br /> | <p>The Registry includes a growing number of parts for use in yeast, but there currently exist no BBa compatible yeast shuttle vectors. In our work, we have chosen to utilize Sikorski yeast vectors to integrate BBa parts into yeast chromosomes. [1] With genomic insertion, each transformation is stable, being reproduced with the rest of the chromosome. Additionally, exactly one copy of each insertion is present in transformed strains, allowing for precise control of the relative expression levels of multiple elements. The Sikorski vectors can be transformed into E. coli for construction and propagation. There exist four integrative vectors in the pRS30x family, each integrating at a different auxotrophic locus and containing the amino acid synthesis gene to fill that auxotrophy as a marker for integration. The vectors are not suitable for Biobrick construction- they each contain one extraneous Biobrick site, and lack the standard cloning site. Thankfully, there is a standard method for cloning BBa parts onto the pRS30x vectors for yeast chromosomal integration: [2] </p><br /> | ||
| + | |||
| + | |||
<ul> | <ul> | ||
| - | <li>Digest the BBa vector containing the finished construct and pRS30x vector of choice using the following enzymes:</li> | + | <li>Digest the BBa vector containing the finished construct and pRS30x vector of choice using the following enzymes:</li><br> |
</ul> | </ul> | ||
<div align="center"> | <div align="center"> | ||
| Line 33: | Line 35: | ||
</tr> | </tr> | ||
</table> | </table> | ||
| + | <br> | ||
</div> | </div> | ||
<p>Alternatively, the final BBa construction ligation can be done as a double insertion onto a pRS30x vector. We did all of our pRS vector insertions this way. The three-way ligations work well consistently, and many variations (e.g. combination of promoters and coding regions) can be generated with relative ease:</p> | <p>Alternatively, the final BBa construction ligation can be done as a double insertion onto a pRS30x vector. We did all of our pRS vector insertions this way. The three-way ligations work well consistently, and many variations (e.g. combination of promoters and coding regions) can be generated with relative ease:</p> | ||
| Line 110: | Line 113: | ||
<ul> | <ul> | ||
<li> Heat-kill and/or purify the digest</li> | <li> Heat-kill and/or purify the digest</li> | ||
| - | <li> | + | <li>Transform the linear construct into a haploid strain with the correct auxotrophies (His, Trp, Leu, Ura- we used W303) using a standard lithium acetate procedure. We have gotten good results from the following:</li> |
</ul> | </ul> | ||
<p><a href="http://www.natureprotocols.com/2007/01/31/highefficiency_yeast_transform.php">http://www.natureprotocols.com/2007/01/31/highefficiency_yeast_transform.php</a></p> | <p><a href="http://www.natureprotocols.com/2007/01/31/highefficiency_yeast_transform.php">http://www.natureprotocols.com/2007/01/31/highefficiency_yeast_transform.php</a></p> | ||
| + | |||
| + | |||
| + | Select for transformants by plating the transformation on a synthetic defined (SD) plate with amino acid dropouts for whatever gene is encoded on the vector you transformed. Double integrations (integrating two constructs at ones) worked very reliably for us, and triple integrations worked about half the time. | ||
| + | |||
| + | If you need to integrate more than four constructs, you can transform up to three into each haploid mating type (a and alpha), then mate them to yield a diploid strain with all of your constructs. Use complementary selection markers (e.g. His, Trp, Leu in type a and Trp, Leu, Ura in type alpha) so you can plate the mixed cells on SD-His-Trp-Leu-Ura and select for cells that have mated, and thus have all of your constructs in their genome. | ||
| + | |||
| + | |||
<p>[1] <a href="http://www.genetics.org/cgi/reprint/122/1/19.pdf" title="http://www.genetics.org/cgi/reprint/122/1/19.pdf">http://www.genetics.org/cgi/reprint/122/1/19.pdf</a><br /> | <p>[1] <a href="http://www.genetics.org/cgi/reprint/122/1/19.pdf" title="http://www.genetics.org/cgi/reprint/122/1/19.pdf">http://www.genetics.org/cgi/reprint/122/1/19.pdf</a><br /> | ||
[2] <a href="http://openwetware.org/wiki/Silver:_BB_Strategy">http://openwetware.org/wiki/Silver:_BB_Strategy</a></p> | [2] <a href="http://openwetware.org/wiki/Silver:_BB_Strategy">http://openwetware.org/wiki/Silver:_BB_Strategy</a></p> | ||
</html> | </html> | ||
Latest revision as of 04:42, 30 October 2008
Moving Biobrick Constructs onto Yeast ChromosomesA New Standard for Biobrick Construction
The Registry includes a growing number of parts for use in yeast, but there currently exist no BBa compatible yeast shuttle vectors. In our work, we have chosen to utilize Sikorski yeast vectors to integrate BBa parts into yeast chromosomes. [1] With genomic insertion, each transformation is stable, being reproduced with the rest of the chromosome. Additionally, exactly one copy of each insertion is present in transformed strains, allowing for precise control of the relative expression levels of multiple elements. The Sikorski vectors can be transformed into E. coli for construction and propagation. There exist four integrative vectors in the pRS30x family, each integrating at a different auxotrophic locus and containing the amino acid synthesis gene to fill that auxotrophy as a marker for integration. The vectors are not suitable for Biobrick construction- they each contain one extraneous Biobrick site, and lack the standard cloning site. Thankfully, there is a standard method for cloning BBa parts onto the pRS30x vectors for yeast chromosomal integration: [2]
Alternatively, the final BBa construction ligation can be done as a double insertion onto a pRS30x vector. We did all of our pRS vector insertions this way. The three-way ligations work well consistently, and many variations (e.g. combination of promoters and coding regions) can be generated with relative ease:
http://www.natureprotocols.com/2007/01/31/highefficiency_yeast_transform.php Select for transformants by plating the transformation on a synthetic defined (SD) plate with amino acid dropouts for whatever gene is encoded on the vector you transformed. Double integrations (integrating two constructs at ones) worked very reliably for us, and triple integrations worked about half the time. If you need to integrate more than four constructs, you can transform up to three into each haploid mating type (a and alpha), then mate them to yield a diploid strain with all of your constructs. Use complementary selection markers (e.g. His, Trp, Leu in type a and Trp, Leu, Ura in type alpha) so you can plate the mixed cells on SD-His-Trp-Leu-Ura and select for cells that have mated, and thus have all of your constructs in their genome.[1] http://www.genetics.org/cgi/reprint/122/1/19.pdf |
