Hi Jacob, They are not too small to mount I think, at least 20 microns long (compared to the size of surrounding cells). But what do you mean by "littered"? There seems to be just one cell with crystals out of say 10 expressing eGFP. And why are there only 10 or so expressing GFP out of ~200 or more cells in the field? This does not look like transient expression using a normal plasmid...
Very intriguing nevertheless! radu ------------------------------------------ A. Radu Aricescu, PhD University Research Lecturer University of Oxford Wellcome Trust Centre for Human Genetics Division of Structural Biology Roosevelt Drive, Oxford OX3 7BN United Kingdom Phone: +44-1865-287564 Fax: +44-1865-287547 ---- Original message ---- >Date: Fri, 15 Feb 2013 14:44:32 -0500 >From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> (on behalf of Jacob Keller ><j-kell...@fsm.northwestern.edu>) >Subject: [ccp4bb] Sighting of Protein Crystals in Vivo?! >To: CCP4BB@JISCMAIL.AC.UK > > Dear Crystallographers, > I was looking at some live, control HEK cells > expressing just eGFP, and to my great surprise, saw > littered across the dish what appeared to be small > fluorescent needles (see attached--sorry about the > size, but it's only ~1MB total.) Can these possibly > be fortuitous protein crystals? They were too small > to mount I think, and for what it's worth, > parallel-transfected HeLa cells did not have these > things. But, some needles could be seen in the DIC > images as well, and the needles were only > fluorescent with GFP filter sets, and not CFP, YFP, > or texas red filters. I thought of whale myoglobin > crystallizing on the decks of ships, but never > thought I would see this.... > Jacob > > -- > ******************************************* > Jacob Pearson Keller, PhD > Postdoctoral Associate > HHMI Janelia Farms Research Campus > email: j-kell...@northwestern.edu > ******************************************* >________________ >GFP_crystals_DIC.png (938k bytes) >________________ >GFP_crystals_Fluorescence.png (586k bytes)
