We release two more Cas9/CRISPR related antibodies, a rabbit polyclonal to Streptococcus pyogenes Cas9, RPCA-Cas9-AP and a mouse monoclonal, MCA-3F9 to the same protein. These can be used to confirm the expression of the most commonly used Cas9 molecule in transfection experiments.
We continue to release antibodies to Cas9, the key enzyme in the CRISPR gene editing system. These are RPCA-Cas9-SA and CPCA-Cas9-SA. These polyclonal antibodies recognize the Cas9 protein from Staphylococcus aureus, which is considerably smaller than the Streptococcus pyogenes derived Cas9. Since the two Cas9 enzymes are quite different in amino acid sequence our antibody to S. aureus does not bind S. pyogenes Cas9, and antibodies to the S. pyogenes form would not be expected to bind S. pyogenes Cas9. We also release a rabbit polyclonal antibody to the human neural stem cell marker Nestin, RPCA-Nestin. We release several biochemical preparations of major CNS proteins. One is purified pig GFAP, Prot-m-GFAP, biochemically isolated from pig spinal cord. This preparation has post-translational modifications absent from our recombinant forms of the same protein based on the human and rodent sequence. These are our Prot-r-GFAP and Prot-r-GFAP-rat products respectively. We also release pure protein preparations of both bovine and porcine derived pNF-H, the phosphorylated axonal form of neurofilament NF-H. These are Prot-m-pNF-H-bov and Prot-m-pNF-H-por.
The life sciences have recently been revolutionized by the exploitation of the bacterial CRISPR system. CRISPR is an acronym for “Clustered Regularly Interspaced Short Palindromic Repeats”. The short palindromes are DNA sequences generated by the bacterial host, while the DNA inserts between them are derived from infectious agents which have previously challenged the bacteria. These inserts generate a complementary RNA which can direct a DNA cutting enzyme, Cas9, to specific base sequences in the DNA of the relevant infectious agents, cutting their DNA and hence inactivating them. Cas9, which means “CRISPR associated protein 9”, was originally studied in Streptococcus pyogenes and is a very large multidomain protein of 158kDa molecular weight. This is inconvenient for many purposes as the DNA needed to express it is correspondingly large, which can present problems with some DNA vector systems. A systematic search for smaller Cas9 homologues showed that Staphylococcus aureus expressed a significantly smaller version, of 124kDa, and we have made a monoclonal antibody to the the C-terminal domain of this, namely MCA-6F7. We also continue to build out our portfolio of antibodies directed against Cnidarian fluorescent proteins, with rabbit antibodies to FP506 (RPCA-FP506) from Zooanthus and EosFP (RPCA-EOSFP) from Lobophyllia hemprichii. Both antibodies are available now. We also release two mouse monoclonals to GFP, MCA-1F1 and MCA-3B11. We add an affinity purified rabbit polyclonal antibody to secretagogin, RPCA-SCGN-ap, to our collection of antibodies to small Calcium binding proteins. These are useful for subclassifying interneurons in the brain. There is a growing interest in the detection of GFAP in blood and CSF as a potential biomarker of CNS damage and disease states. Since the human and rodent proteins have some significant differences at the primary sequence level, we have now expressed full length recombinant rat GFAP, Prot-r-GFAP-rat, which is a more useful protein standard for workers using rodent models. Finally we release an excellent affinity purified antibody to laminin, RPCA-Laminin-ap, which stains blood vessels in the brain beautifully.
January 2016 News
Happy New Year and all that!! We release several more novel immunoreagents. There are no less than 6 different antibodies to complement C3 made against specific subdomains of this important molecule. Three were made against a recombinant form of the netrin domain of human C3 which is at the C-terminus of the α-chain. These are two mouse monoclonals MCA-6E8 and MCA-2B5 and a chicken polyclonal CPCA-C3-Net. Two were made against a recombinant construct including the human anaphylotoxin domain, MCA-6B1 and MCA-7C1. Finally MCA-5F2 was made against full length human complement C3 and binds an epitope in the center of the α-subunit. All work well on western blots and can detect C3 and various fragmented forms in blood samples and tissue extracts. We also release an extremely nice antibody to the heat shock protein HSP60 made in chicken, CPCA-HSP60. This stains mitochondria in a beautiful fashion and is a good western blotting standard as this antibody is extremely clean on western blots.These complement our monoclonal MCA-1C7 and a rabbit polyclonal RPCA-HSP60, both released late last year.