My oligonucleotide does not appear to be the right length when I checked by gel electrophoresis. Why is this?
Oligos should be run on a polyacrylamide gel containing 7 M urea and loaded with a 50% formamide solution to avoid compressions and secondary structures. Oligos of the same length and different compositions can electrophorese differently. dC's migrate fastest, followed by dA's, dT's, and then dG's. Oligos containing N's tend to run as a blurry band and generally have a problem with secondary structure.
The primers I am using worked for PCR initially, but over time, have stopped working. What happened?
Primers should be aliquoted for single use before PCR set-up. Heat just the aliquoted primers to 94 degrees for 1 min. Quick chill the primer on ice before adding to the PCR reaction. Some primers may anneal to themselves or curl up on themselves.
I don't see a pellet in my oligo tube order. Should I ask for a replacement?
The drying method dries the primer in a thin layer along the sidewalls of the tube instead of the bottom, therefore a pellet is not always visible and should still be ready to use.
There is a ball-shaped pellet at the bottom of my oligo tube. What is this and can I still use my oligo?
If the oligo was overheated, it will appear as a ball-shaped pellet attached to the bottom of the tube. This should not affect the quality of the oligo, and the oligo should be readily soluble in water.
There is a green color in my lyophilized oligo. Can I still use it?
If an oligo appears green in color, this is most likely due to ink falling into the tube. The oligo should still be fully functional. The color can be removed by doing an ethanol precipitation.
Quaternary epitope specificities of anti-HIV-1 neutralizing antibodies generated in rhesus macaques infected by the simian/human immunodeficiency virus SHIVSF162P4.
Authors:Robinson JE, Franco K, Elliott DH, Maher MJ, Reyna A, Montefiori DC, Zolla-Pazner S, Gorny MK, Kraft Z, Stamatatos L
Journal:J Virol
PubMed ID:20106929
'Monoclonal antibodies (MAbs) that neutralize human immunodeficiency virus type 1 (HIV-1) have been isolated from HIV-1-infected individuals or animals immunized with recombinant HIV-1 envelope (Env) glycoprotein constructs. The epitopes of these neutralizing antibodies (NAbs) were shown to be located on either the variable or conserved regions of the HIV-1 Env ... More
Ultraviolet-B-mediated induction of protein-protein interactions in mammalian cells.
Light-sensitive proteins are useful tools to control protein localization, activation and gene expression, but are currently limited to excitation with red or blue light. Here we report a novel optogenetic system based on the ultraviolet-B-dependent interaction of the Arabidopsis ultraviolet-B photoreceptor UVR8 with COP1 that can be performed in visible ... More