Tyrosine hydroxylase /mRNA expression in the honey bee brain
This is the expression pattern for the gene that encodes the rate-limiting enzyme in dopamine synthesis, tyrosine hydroxylase (th; green), in the brain of a forager honey bee. We used whole-mount fluorescent in situ hybridization and then generated this image from the maximum intensity pixels from a set of optical sections through the entire brain. Optical sections were captured using a Zeiss LSM 700 confocal microscope and compiled using ImageJ software. The signal was generated with a method newly developed in the laboratory of Sanjay Tyagi (University of Medicine and Dentistry of New Jersey) that uses a series of 48 anti-sense DNA probes, all targeted to the th mRNA transcript, with each DNA probe labeled with a single fluorescent molecule (Quasar 570). This approach for processing whole tissues is novel because it does not rely upon enzymatic amplification of the fluorescence signal, thus significantly reducing processing time. By combining this method with an automation feature on the confocal microscope available in the IGB Core Facilities, we are able to image over 250 brains in one month. A couple of key brain regions are labeled as follows. ol: optic lobes; mb: Mushroom Bodies, a region of the insect brain involved in learning and memory.
