Glucose-regulated protein 78 binds to and regulates the melanocortin-4 receptor.

The melanocortin-4 receptor (MC4R) belongs to the G protein-coupled receptor (GPCR) family and plays an essential role in the control of energy homeostasis. Here, we identified a novel MC4R-interacting protein, glucose-regulated protein 78 (GRP78), from a pulldown assay using hypothalamic protein extracts and the third intracellular loop of MC4R. We found that MC4R interacted with GRP78 in both the cytosol and at the cell surface and that this interaction increased when MC4R was internalized in the presence of the agonist melanotan-II (MTII).

Hypomyelination and cognitive impairment in mice lacking CD133 (Prominin-1).

The CD133 antigen, also known as prominin-1, is a glycoprotein that specifically localizes to plasma membrane protrusions. The precise function of CD133 remains unknown, but it is expressed in various progenitor cells including those derived from the neural and hematopoietic system, as well as different tissues. In the adult mouse brain, CD133 is highly expressed in white matter.

Publisher Correction: Role of Dopamine D2 Receptor in Stress-Induced Myelin Loss.

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Role of Dopamine D2 Receptor in Stress-Induced Myelin Loss.

Dopaminergic systems play a major role in reward-related behavior and dysregulation of dopamine (DA) systems can cause several mental disorders, including depression. We previously reported that dopamine D2 receptor knockout (D2R) mice display increased anxiety and depression-like behaviors upon chronic stress. Here, we observed that chronic stress caused myelin loss in wild-type (WT) mice, while the myelin level in D2R mice, which was already lower than that in WT mice, was not affected upon stress.

Melanocortin 4 Receptor and Dopamine D2 Receptor Expression in Brain Areas Involved in Food Intake.

Background: The melanocortin 4 receptor (MC4R) is involved in the regulation of homeostatic energy balance by the hypothalamus. Recent reports showed that MC4R can also control the motivation for food in association with a brain reward system, such as dopamine. We investigated the expression levels of MC4R and the dopamine D2 receptor (D2R), which is known to be related to food rewards, in both the hypothalamus and brain regions involved in food rewards.

Enhanced hypothalamic leptin signaling in mice lacking dopamine D2 receptors.

The dopamine D(2) receptor (D2R) plays a critical role in diverse neurophysiological functions. D2R knock-out mice (D2R(-/-)) show reduced food intake and body weight while displaying an increased basal energy expenditure level, compared with their wild type littermates. Thus, these mice show a lean phenotype.