Different structural requirements for melanin-concentrating hormone (MCH) interacting with rat MCH-R1 (SLC-1) and mouse B16 cell MCH-R.

Melanin-concentrating hormone (MCH) is a neuropeptide occurring in all vertebrates and some invertebrates and is now known to stimulate pigment aggregation in teleost melanophores and food-intake in mammals. Whereas the two MCH receptor subtypes hitherto cloned, MCH-R1 and MCH-R2, are thought to mediate mainly the central effects of MCH, the MCH-R on pigment cells has not yet been identified, although in some studies MCH-R1 was reported to be expressed by human melanocytes and melanoma cells. Here we present data of a structure-activity study in which 12 MCH peptides were tested on rat MCH-R1 and mouse B16 melanoma cell MCH-R, by comparing receptor binding affinities and biological activities.

Expression of receptors for melanin-concentrating hormone (MCH) in different tissues and cell lines.

Melanin-concentrating hormone (MCH) is a potent orexigenic neuropeptide and a physiological antagonist of alpha-melanocyte-stimulating hormone (alpha-MSH) in the brain as well as at peripheral sites, including the pigmentary systems of specific vertebrates. Two receptor subtypes for MCH, MCH-R1 and MCH-R2, have been cloned, but other receptor subtypes are likely to exist. Based on our own data and the current literature, we have compared the expression of different receptors for MCH in various mammalian cell lines and tissues.

Endogenous receptor for melanin-concentrating hormone in human neuroblastoma Kelly cells.

Melanin-concentrating hormone (MCH), a cyclic nonadecapeptide, is predominantly expressed in mammalian neurons located in the zona incerta and lateral hypothalamus. Current interest in MCH relates to its role in the control of feeding behaviour. Two receptors for MCH were recently found: MCH-R(1) and MCH-R(2).

Sp100 interacts with ETS-1 and stimulates its transcriptional activity.

The cell nucleus is highly organized into distinct domains that spatially separate physiological processes. One of these domains, the Sp100-promyelocytic leukemia protein nuclear body (NB), is implicated in pathological processes, such as cancer and viral infection, yet its functions remain poorly understood. We show here that Sp100 interacts physically and functionally with ETS-1 and that NB morphology is affected by ETS-1.