The roleof the catecholaminergic…
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Figure 4. Techniques to manipulate gene expression in the chick embryo: implanted
microbeads and electroporation.
A) The stage 3-‐5 blastoderm can be accessed
in ovo
and B) a
factor-‐coatedmicrobead (yellowcircle) canbe implantedat thedesired location lateral to theheart
field of one side (blue square). After 6-‐18 h of further incubation the embryo can be retrieved and
processed for RNA or protein detection. C) The blastoderm can also be placed in culture and
injected and electroporatedwith DNA constructs, such as that shown in schematic form, inwhich
the sequences of TH and the green fluorescence protein (GFP) are linked by an IRES (Internal
Ribosome Entry Site). After 18-‐36 h of additional incubation, embryos can be collected and
processed.
