Basal adrenocorticotropin (ACTH) secretion is negatively modulated by protein phosphatase 5 in mouse pituitary corticotropin AtT20 cells. 2005

Feng Liu, and Xavier Khawaja
Department of Neuroscience, Wyeth Research, 865 Ridge Road, Monmouth Junction, NJ 08852, USA.

siRNA oligonucleotides for protein phosphatase 5 (PP5) were designed and transfected into mouse corticotroph AtT20 cells to induce lower PP5 expression levels. PP5-siRNA transfections (at 3 days) produced a approximately 50% down-regulation in targeted protein levels. PP5-underexpressing cells released significantly more ir-ACTH (10-12-fold) relative to baseline levels and promoted POMC release into the media. Neither CRF-mediated ACTH release nor dexamethasone-induced ACTH repression were affected in PP5-siRNA transfected cells. In summary, our observations suggest that endogenous PP5 can exert a negative modulatory effect on basal ACTH release in neurosecretion-competent AtT20 cells through a mechanism as yet unknown but which does not directly involve regulated CRF or glucocorticoid receptor-dependent pathways. However, PP5 may cause mis-sorting of POMC and POMC-derived peptides at the constitutive-like secretory pathway level in an unregulated manner. Such a missorting could lead to impaired processing of POMC.

UI MeSH Term Description Entries
D009687 Nuclear Proteins Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus. Nucleolar Protein,Nucleolar Proteins,Nuclear Protein,Protein, Nuclear,Protein, Nucleolar,Proteins, Nuclear,Proteins, Nucleolar
D010749 Phosphoprotein Phosphatases A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992) Phosphoprotein Phosphatase,Phosphoprotein Phosphohydrolase,Protein Phosphatase,Protein Phosphatases,Casein Phosphatase,Ecto-Phosphoprotein Phosphatase,Nuclear Protein Phosphatase,Phosphohistone Phosphatase,Phosphoprotein Phosphatase-2C,Phosphoseryl-Protein Phosphatase,Protein Phosphatase C,Protein Phosphatase C-I,Protein Phosphatase C-II,Protein Phosphatase H-II,Protein-Serine-Threonine Phosphatase,Protein-Threonine Phosphatase,Serine-Threonine Phosphatase,Threonine Phosphatase,Ecto Phosphoprotein Phosphatase,Phosphatase C, Protein,Phosphatase C-I, Protein,Phosphatase C-II, Protein,Phosphatase H-II, Protein,Phosphatase, Casein,Phosphatase, Ecto-Phosphoprotein,Phosphatase, Nuclear Protein,Phosphatase, Phosphohistone,Phosphatase, Phosphoprotein,Phosphatase, Phosphoseryl-Protein,Phosphatase, Protein,Phosphatase, Protein-Serine-Threonine,Phosphatase, Protein-Threonine,Phosphatase, Serine-Threonine,Phosphatase, Threonine,Phosphatase-2C, Phosphoprotein,Phosphatases, Phosphoprotein,Phosphatases, Protein,Phosphohydrolase, Phosphoprotein,Phosphoprotein Phosphatase 2C,Phosphoseryl Protein Phosphatase,Protein Phosphatase C I,Protein Phosphatase C II,Protein Phosphatase H II,Protein Phosphatase, Nuclear,Protein Serine Threonine Phosphatase,Protein Threonine Phosphatase,Serine Threonine Phosphatase
D010902 Pituitary Gland A small, unpaired gland situated in the SELLA TURCICA. It is connected to the HYPOTHALAMUS by a short stalk which is called the INFUNDIBULUM. Hypophysis,Hypothalamus, Infundibular,Infundibular Stalk,Infundibular Stem,Infundibulum (Hypophysis),Infundibulum, Hypophyseal,Pituitary Stalk,Hypophyseal Infundibulum,Hypophyseal Stalk,Hypophysis Cerebri,Infundibulum,Cerebri, Hypophysis,Cerebrus, Hypophysis,Gland, Pituitary,Glands, Pituitary,Hypophyseal Stalks,Hypophyses,Hypophysis Cerebrus,Infundibular Hypothalamus,Infundibular Stalks,Infundibulums,Pituitary Glands,Pituitary Stalks,Stalk, Hypophyseal,Stalk, Infundibular,Stalks, Hypophyseal,Stalks, Infundibular
D002460 Cell Line Established cell cultures that have the potential to propagate indefinitely. Cell Lines,Line, Cell,Lines, Cell
D003346 Corticotropin-Releasing Hormone A peptide of about 41 amino acids that stimulates the release of ADRENOCORTICOTROPIC HORMONE. CRH is synthesized by neurons in the PARAVENTRICULAR NUCLEUS of the HYPOTHALAMUS. After being released into the pituitary portal circulation, CRH stimulates the release of ACTH from the PITUITARY GLAND. CRH can also be synthesized in other tissues, such as PLACENTA; ADRENAL MEDULLA; and TESTIS. ACTH-Releasing Hormone,CRF-41,Corticotropin-Releasing Factor,Corticotropin-Releasing Hormone-41,ACTH-Releasing Factor,CRF (ACTH),Corticoliberin,Corticotropin-Releasing Factor-41,ACTH Releasing Factor,ACTH Releasing Hormone,Corticotropin Releasing Factor,Corticotropin Releasing Factor 41,Corticotropin Releasing Hormone,Corticotropin Releasing Hormone 41
D000324 Adrenocorticotropic Hormone An anterior pituitary hormone that stimulates the ADRENAL CORTEX and its production of CORTICOSTEROIDS. ACTH is a 39-amino acid polypeptide of which the N-terminal 24-amino acid segment is identical in all species and contains the adrenocorticotrophic activity. Upon further tissue-specific processing, ACTH can yield ALPHA-MSH and corticotrophin-like intermediate lobe peptide (CLIP). ACTH,Adrenocorticotropin,Corticotropin,1-39 ACTH,ACTH (1-39),Adrenocorticotrophic Hormone,Corticotrophin,Corticotrophin (1-39),Corticotropin (1-39),Hormone, Adrenocorticotrophic,Hormone, Adrenocorticotropic
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D051379 Mice The common name for the genus Mus. Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus
D034741 RNA, Small Interfering Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions. RNA, Scan,Repeat-Associated siRNA,Scan RNA,Small Scan RNA,Trans-Acting siRNA,siRNA,siRNA, Repeat-Associated,siRNA, Trans-Acting,Short Hairpin RNA,Short Interfering RNA,Small Hairpin RNA,Small Interfering RNA,scnRNA,shRNA,tasiRNA,Hairpin RNA, Short,Hairpin RNA, Small,Interfering RNA, Short,Interfering RNA, Small,RNA, Short Hairpin,RNA, Short Interfering,RNA, Small Hairpin,RNA, Small Scan,Repeat Associated siRNA,Scan RNA, Small,Trans Acting siRNA,siRNA, Repeat Associated,siRNA, Trans Acting

Related Publications

Feng Liu, and Xavier Khawaja
May 2015, Brain research,
Feng Liu, and Xavier Khawaja
October 1991, European journal of pharmacology,
Feng Liu, and Xavier Khawaja
August 2013, Molecular and cellular endocrinology,
Feng Liu, and Xavier Khawaja
October 1982, Proceedings of the National Academy of Sciences of the United States of America,
Copied contents to your clipboard!