Talk:Digoxigenin

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''It can easily be attached to oligonucleotides, at either 5' or 3' ends by chemical modifications.

''To detect mRNA production in a given cell :

''1- Prepare complimentary RNA with DIG attached to them. Nowadays, you order that over the internet.

''2- Following your preferred protocol for In situ hybridization, attach this probe to mRNA produced by the cell.

''3- Use an anti-DIG antibody to detect DIG (and hence, mRNA). ''

This is basically rubbish. I'm not sure how Dig is attached, but it's usually conjugated to a specific nucleotide (normally Uridine) which is incorporated into the complimentary mRNA when it's synthesised - therefore attaching it to the bits where nucleotides join together into strands is unlikely.

Nobody in their right mind would order RNA over the internet; everyone but everyone produces their mRNA fragments in house. Presumably whoever wrote this is getting confused with primer design, which is (as far as I'm aware) largely done online; given oligonucleotide primers (10-20 nucleotides) and a cDNA library or a complete set of genomic DNA, you can produce a large number of gene fragments (commonly 100-1000 nucleotides) using PCR; which is usually put in a plasmid. You then use an RNA polymerase, and a nucleotide mix containing only Dig-labelled Uridine triphosphate, to make a transcript that can be detected by antibody.

It can also be conjugated to specific sugars and allowed to incorporate into glycoproteins in live cells, and detected by anti-Dig antibodies.

Am updating to reflect this, and to make it read less like a protocol for ISH.

Confuseddave 20:03, 12 January 2007 (UTC)

Should the first line say antigenicity instead of immunogenicity? I thought that haptens only elicited immune responses when conjugated to larger moleculars

99.231.52.177 (talk) 05:06, 28 January 2009 (UTC)

PubChem says that Digoxigenin can be isolated from D. orientalis and D. lanata, making no mention of D. purpurea. I don't know what the truth is here, but it would seem that, at the very least, "exclusively" isn't the right word to use here. Looked it up in Biochemical targets of plant bioactive compounds by Gideon Maxwell Polya (it's on Google Books) and it turns out digoxigenin present in all 3.

Dewert (talk) 16:43, 21 July 2009 (UTC)