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Kisspeptin
Kisspeptins (including kisspeptin-54 (KP-54), formerly known as metastin) are proteins encoded by the ''KISS1'' gene in humans. Kisspeptins are ligands of the G-protein coupled receptor, GPR54. ''Kiss1'' was originally identified as a human metastasis suppressor gene that has the ability to suppress melanoma and breast cancer metastasis. Kisspeptin-GPR54 signaling has an important role in initiating secretion of gonadotropin-releasing hormone (GnRH) at puberty, the extent of which is an area of ongoing research. Gonadotropin-releasing hormone is released from the hypothalamus to act on the anterior pituitary triggering the release of luteinizing hormone (LH), and follicle stimulating hormone (FSH). These gonadotropic hormones lead to sexual maturation and gametogenesis. Disrupting GPR54 signaling can cause hypogonadotrophic hypogonadism in rodents and humans. The Kiss1 gene is located on chromosome 1. It is transcribed in the brain, adrenal gland, liver, gonads, and pancreas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KiSS1-derived Peptide Receptor
The KiSS1-derived peptide receptor (also known as GPR54 or the Kisspeptin receptor) is a G protein-coupled receptor which binds the peptide hormone kisspeptin (metastin). Kisspeptin is encoded by the metastasis suppressor gene KISS1, which is expressed in a variety of endocrine and gonadal tissues. Activation of the kisspeptin receptor is linked to the phospholipase C and inositol trisphosphate second messenger cascades inside the cell. Kisspeptins are neuropeptides synthesized in the hypothalamus and encoded by the KISS1 gene. The KISS1 gene encodes the G protein-coupled receptor 54 (known as KISS1R or GPR54) and plays a crucial role in regulating reproduction, pubertal maturation, and metabolic function. KISS1 neurons located in the arcuate nucleus (ARC) of the mediobasal hypothalamus (MBH) project to GnRH neurons in the median eminence, which expresses KISS1R, to stimulate LH secretions in a pulsatile manner from the anterior pituitary to initiate ovulation/ pubertal matura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles in a male. In response to the signals, the gonads produce hormones that stimulate libido and the growth, function, and transformation of the brain, bones, muscle, blood, skin, hair, breasts, and sex organs. Physical growth—height and weight—accelerates in the first half of puberty and is completed when an adult body has been developed. Before puberty, the external sex organs, known as primary sexual characteristics, are sex characteristics that distinguish males and females. Puberty leads to sexual dimorphism through the development of the secondary sex characteristics, which further distinguish the sexes. On average, females begin puberty at age 10½ and complete puberty at ages 15-17; males begin at ages 11½-12 and complete pube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danny Welch
Danny Ray Welch is an American cancer biologist and founding director of the University of Kansas Medical Center's Department of Cancer Biology. Welch is also a professor at the University of Kansas School of Medicine and director of the National Foundation for Cancer Research (NFCR) Center for Metastasis Research at KU. His research is in the area of metastasis suppressor genes and the biology of metastasis. He is known for his discovery of a number of metastasis suppressor genes. By definition, these genes suppress metastasis without suppressing growth of the primary tumor. He is also well known for his work in defining the characters of cancer metastasis, and for his mentoring. In 1996, Welch's lab in Hershey, Pennsylvania, isolated a cDNA from a cancer cell that was not able to undergo metastasis after the human chromosome 6 was added to the cell. This gene was named ''KISS1'' because of the location of where it was discovered (Hershey, Pennsylvania, home of Hershey's Kisses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonadotropin-releasing Hormone
Gonadotropin-releasing hormone (GnRH) is a releasing hormone responsible for the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. GnRH is a tropic peptide hormone synthesized and released from GnRH neurons within the hypothalamus. GnRH is inhibited by testosterone. The peptide belongs to gonadotropin-releasing hormone family. It constitutes the initial step in the hypothalamic–pituitary–gonadal axis. Structure The identity of GnRH was clarified by the 1977 Nobel Laureates Roger Guillemin and Andrew V. Schally: pyroGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2 As is standard for peptide representation, the sequence is given from amino terminus to carboxyl terminus; also standard is omission of the designation of chirality, with assumption that all amino acids are in their L- form. The abbreviations are the standard abbreviations for the corresponding proteinogenic amino acids, except for ''pyroGlu'', whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luteinizing Hormone
Luteinizing hormone (LH, also known as luteinising hormone, lutropin and sometimes lutrophin) is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. In females, an acute rise of LH known as an LH surge, triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell–stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone. It acts synergistically with follicle-stimulating hormone ( FSH). Etymology The term luteinizing comes from the Latin "luteus", meaning "yellow". This is in reference to the corpus luteum, which is a mass of cells that forms in an ovary after an ovum (egg) has been discharged. The corpus luteum is so named because it often has a distinctive yellow color. The process of forming the corpus luteum is known as " luteinization", and thus the hormone that triggers th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypogonadotrophic Hypogonadism
Hypogonadotropic hypogonadism (HH), is due to problems with either the hypothalamus or pituitary gland affecting the hypothalamic-pituitary-gonadal axis (HPG axis). Hypothalamic disorders result from a deficiency in the release of gonadotropic releasing hormone (GnRH), while pituitary gland disorders are due to a deficiency in the release of gonadotropins from the anterior pituitary. GnRH is the central regulator in reproductive function and sexual development via the HPG axis. GnRH is released by GnRH neurons, which are hypothalamic neuroendocrine cells, into the hypophyseal portal system acting on gonadotrophs in the anterior pituitary. The release of gonadotropins, LH and FSH, act on the gonads for the development and maintenance of proper adult reproductive physiology. LH acts on Leydig cells in the male testes and theca cells in the female. FSH acts on Sertoli cells in the male and follicular cells in the female. Combined this causes the secretion of gonadal sex steroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endogenous
Endogeny, in biology, refers to the property of originating or developing from within an organism, tissue, or cell. For example, ''endogenous substances'', and ''endogenous processes'' are those that originate within a living system (e.g. an organism or a cell). For instance, estradiol is an endogenous estrogen hormone A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physio ... produced within the body, whereas ethinylestradiol is an exogenous synthetic estrogen, commonly used in birth control pills. In contrast, '' exogenous substances'' and ''exogenous'' ''processes'' are those that originate from outside of an organism. References External links *{{Wiktionary-inline, endogeny Biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligands
In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication ( translesion synthesis). Mutations may also result from substitution, insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics ( phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein Coupled Receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large protein family, group of evolutionarily related proteins that are cell surface receptors that detect molecules outside the cell (biology), cell and activate cellular responses. They are coupled with G proteins. They pass through the cell membrane seven times in the form of six loops (three extracellular loops interacting with ligand molecules, three intracellular loops interacting with G proteins, an N-terminus, N-terminal extracellular region and a C-terminal intracellular region) of amino acid residues, which is why they are sometimes referred to as seven-transmembrane receptors. Text was copied from this source, which is available under Attribution 2.5 Generic (CC BY 2.5) licence/ref> Ligands can bind either to the extracellular N-terminus and loops (e.g. glutama ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
