Embryo GFP Strain

Model Organism: Worms Methods & Reagents
1

Hey Everyone,

Does anyone know of a strain that expresses GFP or mCherry not fused to anything in embryos? I’ve only been able to find fused proteins in the databanks… I don’t mind if it also expresses anywhere else as long as it expresses GFP or mCherry not fused to any other protein from 1 or 2 cell stage on!

Thanks for the help!

2

Hi,
I dont know what is your purpose. But if u want to express GFP in all cells better select some housekeeping gene like
beta actin or tubulin labelled proteins,
and still if you want to express it without protein or randomly
try to do microinjection with some vector which divides along with the cell.
I think this will be helpful.

3

According to one source I glanced at, Ryan Baugh’s 2003 Development paper, there’s this, from the Introduction:

Embryonic transcription is first detected in somatic blastomeres at the four-cell stage (Edgar et al., 1994; Hope, 1991; Seydoux and Fire, 1994; Seydoux et al., 1996)
and this, from the Results:
Consistent with expectations from previous work (Edgar et al., 1994; Seydoux and Fire, 1994; Seydoux et al., 1996), relatively few transcripts changed between the one-cell and early four-cell stage
This would seem to be a challenge for a project requiring zygotic transgene expression in the one and two cell stages, though this is not an area I know a lot about and there might be new information since then, or even established transgenes known to express that early. You could find out what genes correspond to those “relatively few transcripts” mentioned in Baugh’s paper, and they might work. Or you might try directly contacting people knowledgeable about expression in the very early elegans embryo directly, and seeing if they have advice to offer.

4

What’s the reason to not have it tagged to another protein? There is a strain (JIM113) that has RFP-tagged histone for nuclear localization that expresses from 1-cell until hatching (using two different transgenes with two different promoters). Or you could search the miniMos transgenic strain list for something that uses the eft-3 promoter to drive GFP with an NLS (and not H2B) or dTomato (for example, EG7986). These usually express ubiquitously from the 1-cell stage, but there is strain to strain variability and they’re not all healthy. The strains are available from the CGC.

5

There is also Dan Dickinson’s gorgeous mNG::his-72. Every nucleus perfectly defined. PMID: 26044593

PS A couple of people in my lab are going to re-make this with red and blue tags.