Contribution of Neural Crest Cells to the Formation of Pituitary Vascular System
USC Biology professor Shannon Davis studies the development of neural crest cells and their contribution to a variety of tissues, including the pituitary gland and skin pigmentation. Neural crest cells (green) form many structures in the head of a developing mouse embryo (red). Defects in neural crest cell formation can cause pigmentation problems, such as in this juvenile deer mouse.
In a current study, Shannon Davis is studying how Neural Crest cells contribute to the formation of the pituitary vascular system, which allows our pituitary endocrine cells to receive the hormonal signals from the brain, and to deliver their own hormones to the rest of the body. Below, you can see the blood vessels (green) in the developing pituitary and brain in the image on the left. A protein called β-catenin is expressed in all cells. In the image on the right you can see β-catenin expression (green) in the pituitary gland and surrounding tissues. Shannon has determined that if β-catenin is removed from the neural crest cells the pituitary vascular system does not develop properly. Research on this and other pituitary development projects is ongoing.
The pituitary gland is often called the master gland because of its central role in regulating many physiological processes. Through the secretion of hormones, such as growth hormone (GH), the pituitary gland regulates growth, reproduction, stress response, and metabolism. Mutations in genes that control pituitary development can result in a pituitary hormone deficiency, or hypopituitarism. People with Combined Pituitary Hormone Deficiency (CPHD) have a deficiency in GH, leading to short stature, and a deficiency in at least one other hormone, which results in a deficiency of metabolism, reproduction, or milk production. One in 8,000 people are affected by CPHD worldwide.
Neural Crest cells originate early in development, along the top of the neural tube. But the Neural Crest cells migrate away from the neural tube forming much of our peripheral nervous system. The neural crest also contribute to other tissues, especially in the head where they differentiate into and/or contribute significantly to a wide range of tissues including melanocytes, cartilage and connective tissue, bones, muscles, cranial nerves, olfactory and auditory sensory organs... and the blood vessels of pituitary gland.
All images associated with this vignette were provided by Shannon Davis.