GSR Microarrays Functional Genomics
GSR Microarrays now offers support for investigators interested in functional genomics or gene manipulation. New technologies offered are RNA interference (RNAi) and full-length cDNA clones suitable for gene over-expression in human and mouse.
RNA interference describes the process in which double-stranded RNA induces the degradation of specific mRNA transcripts. First, an enzyme called Dicer processes the double-stranded RNA into siRNAs (small interfering RNAs), which are short (20-25nt) dsRNA fragments with 2nt overhangs. Then, the siRNAs associate with a protein complex called RISC (RNA-induced silencing complexes), unwinding in the process. The siRNA/RISC complex targets an mRNA transcript with complementary sequence, cleaving and destroying the transcript, effectively "knocking down" the expression of the protein encoded by that mRNA. Long double-stranded RNA molecules cannot be introduced into mammalian cells without eliciting an anti-viral response. The use of viral vectors can bypass this restriction and introduce siRNAs into cells.
The Ambion website provides many resources for RNAi, including a detailed overview and a guide for interested investigators. The RNAi entry on Wikipedia is another good source of information.
GSR Microarrays Inventory
GSR Microarrays carries several RNAi and cDNA libraries from Open Biosystems:
- GIPZ Lentiviral shRNAmir library: The vector used in this library provides a high titer virus with a GFP tag, among other unique vector elements
- pCMV-GIN-ZEO Lentiviral shRNAmir library: This library is being phased out by Open Biosystems in favor of the GIPZ library. GIPZ library production is ongoing and is the preferred library due to higher transfection efficiency, but CMV-GIN-ZEO clones are still available through GSR Microarrays.
- Mammalian Gene Collection cDNA library: A collection of full-length, sequence verified clones.
GSR Microarrays RNAi searchable database contains information on the GIPZ and CMV-GIN-ZEO libraries as well as two additional libraries. The Open Biosystems pSM2 Retroviral shRNAmir library is the source library for GIPZ (clones from this library are being transferred into the GIPZ vector). The other searchable library is compiled by The RNAi Consortium (TRC). GSR Microarrays does not distribute clones from the pSM2 and TRC libraries, but information on them is provided to aid users in making the best selection for their experiments.
Ordering RNAi or cDNA clones from GSR Microarrays
Clones may only be provided to Vanderbilt investigators.
Users must have a GSR Microarrays account to order clones. Once logged in, the RNAi and cDNA Search Tools can be accessed on the right toolbar. You may search by a variety of gene and protein identifiers, as well as more generic terms like partial gene names. As clones are selected, they will appear in the shopping cart located in the upper right-hand corner of the page. When the order is complete, it can be submitted by clicking the "Checkout" button in the shopping cart. Then, billing information may be entered and the order completed.
Clones are provided as frozen glycerol stocks (8% glycerol). Clones are picked the first and third Wednesday of each month. If clones fail to grow, the investigator will be notified. Open Biosystems does not replace clones that do not grow. Investigators can order clones that do not grow, or that are not stocked by the GSR, directly from Open Biosystems using the Vanderbilt discount with Open Biosystems. Please e-mail the GSR for more information regarding the discount.