Hypothalamic LPXRF-amide peptides in vertebrates: identification, localization and hypophysiotropic activity.
Probing undiscovered neuropeptides that play important roles in the regulation of pituitary function in vertebrates is essential for the progress of neuroendocrinology. Recently, we identified a novel hypothalamic neuropeptide with a C-terminal LPLRF-amide sequence in the quail brain. This avian neuropeptide was shown to be located in the hypothalamo-hypophysial system and to decrease gonadotropin release from cultured anterior pituitary. We, therefore, designated this novel neuropeptide as gonadotropin-inhibitory hormone (GnIH). We further identified novel hypothalamic neuropeptides closely related to GnIH in the brains of other vertebrates, such as mammals, amphibians, and fish. The identified neuropeptides possessed a LPXRF-amide (X = L or Q) motif at their C-termini. These LPXRF-amide peptides also were localized in the hypothalamus and other brainstem areas and regulated pituitary hormone release. Subsequently, cDNAs that encode LPXRF-amide peptides were characterized in vertebrate brains. In this review, we summarize the identification, localization, and hypophysiotropic activity of these newly identified hypothalamic LPXRF-amide peptides in vertebrates.
Tsutsui
Kazuyoshi
K
Laboratory of Brain Science, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan. tsutsui@hiroshima-u.ac.jp
Ukena
Kazuyoshi
K
D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins / Q000502:physiology*; D001923:Brain Chemistry; D002645:Chickens; D003001:Cloning, Molecular; D003370:Coturnix; D007028:Hypothalamic Hormones / Q000502:physiology*; D008969:Molecular Sequence Data; D010902:Pituitary Gland / Q000187:drug effects; D011892:Rana catesbeiana; D043562:Receptors, G-Protein-Coupled / Q000302:isolation & purification; D016415:Sequence Alignment; D046370:Sparrows
D030161:Avian Proteins; D007028:Hypothalamic Hormones; D043562:Receptors, G-Protein-Coupled; C413752:gonadotropin-inhibitory hormone, Coturnix japonica