All the colours of the rainbow.

So the "brainbow" paper is finally out. Sanes & Lichtman and co-workers published a paper in Nature (1st Nov 2007) with beautiful images of what might be called their "second generation" GFP mice. In 2000 they introduced their "simple" GFP mice in which they created mice lines with different populations of neurons stained. Now they have created multi-coloured neurons using mixing of RFP, YFP and CFP in a random way. The results are visually stunning (see pic from Supp Fig 2). Unfortunately most of us do not have the microscopes which will allow us to see these colours. You will need 3 PMTs or a CCD colour camera. These mice are a revolution.

Livet J, Weissman TA, Kang H, Draft RW, Lu J, Bennis RA, Sanes JR, Lichtman JW Transgenic strategies for combinatorial expression of fluorescent proteins in the nervous system. Nature (2007) 450 (7166):56-62.

Feng G, Mellor RH, Bernstein M, Keller-Peck C, Nguyen QT, Wallace M, Nerbonne JM, Lichtman JW, Sanes JR Imaging neuronal subsets in transgenic mice expressing multiple spectral variants of GFP. Neuron (2000) 28:41-51