Many cells in our body have a single primary cilium, a micrometer-long, hair-like organelle protruding from the cell surface that transmits cellular signals. Cilia are important for regulating cellular processes, but because of their small size and number, it has been difficult for scientists to explore cilia in brain cells with traditional techniques, leaving their organization and function unclear.

In a series of papers appearing in Current Biology, the Journal of Cell Biology, and the Proceedings of the National Academy of Sciences, researchers at HHMI’s Janelia Research Campus, the Allen Institute, the University of Texas Southwestern Medical Center, and Harvard Medical School used super high-resolution 3D electron microscopy images of mouse brain tissue generated for creating connectomes to get the best look yet at primary cilia.

Researchers have discovered that neurotransmitters like dopamine.

Dopamine is a crucial neurotransmitter involved in many important functions in the brain, particularly those related to pleasure, reward, motivation, and motor control. It plays a central role in the brain’s reward system, where it helps reinforce rewarding behaviors by increasing pleasure and satisfaction, making it critical for habit formation and addictive behaviors. Dopamine is also vital for regulating movement, and deficiencies in dopamine production are linked to neurological disorders such as Parkinson’s disease. Additionally, dopamine influences various other functions, including mood regulation, learning, and attention, making it a key focus in studies of both mental health and neurodegenerative diseases.