Biomaterial Database

Physiologically induced Fos expression in the hypothalamo-hypophyseal system of Xenopus laevis. 1997

R Ubink, and B G Jenks, and E W Roubos

Department of Cellular Animal Physiology, Nijmegen Institute for Neurosciences, University of Nijmegen, The Netherlands. rubink@sci.kun.nl

The amphibian Xenopus laevis adjusts the color of its skin to the degree of background illumination. The neuroendocrine mechanism responsible for this adaptation behavior involves various brain centers that control the synthesis and release of alpha-melanophore-stimulating hormone (alpha-MSH) by the pituitary melanotrope cells. The aim of the present study was to investigate the possible use of Fos as a tool to determine the activity of known and novel components of this mechanism. For this purpose, a quantitative Fos-immunocytochemical method (ABC) was successfully introduced for Xenopus, and the degree of specificity of background illumination as a regulator of Fos expression was tested by comparing this stimulus with two other stimuli, viz. a strong stressor (saline immersion) and a mild stressor ('handling'). Without stimulation basal Fos-like immunoreactivity (Fos-LI) was found in the telencephalon, the lateral pallium, the anterior, central and lateral thalamic nuclei, the suprachiasmatic nucleus, the ventral hypothalamic nucleus and the torus semicircularis. Handling had no effect on this basal pattern of Fos-LI. Saline immersion induced Fos-LI only in the magnocellular preoptic nucleus, the corticotrope cells and, less strongly, in the melanotrope cells. Melanotropes, and no other cells, expressed Fos-LI very strongly when Xenopus was transferred from a white to a black background. This Fos-LI expression continued to increase up to 7 days of stimulation. When such toads were returned to a white background it took the same time before Fos-LI expression significantly dropped. It is concluded that the ABC-Fos immunocytochemistry can be successfully applied to assess the occurrence and degree of expression of Fos-LI in the Xenopus brain and pituitary gland. The prolonged expression of Fos-LI in the pars intermedia under black background stimulation and the presence of an AP-1 binding site on the Xenopus proopiomelanocortin gene suggest an important role for c-Fos and/or Fos-related antigens in the control of the biosynthesis and secretion of alpha-MSH by the Xenopus melanotrope cell.

UI	MeSH Term	Description	Entries
D007031	Hypothalamus	Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE.	Lamina Terminalis,Preoptico-Hypothalamic Area,Area, Preoptico-Hypothalamic,Areas, Preoptico-Hypothalamic,Preoptico Hypothalamic Area,Preoptico-Hypothalamic Areas
D007101	Immersion	The placing of a body or a part thereof into a liquid.	Submersion,Immersions,Submersions
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
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
D003116	Color	The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.	Colors
D006234	Handling, Psychological	Physical manipulation of animals and humans to induce a behavioral or other psychological reaction. In experimental psychology, the animal is handled to induce a stress situation or to study the effects of "gentling" or "mothering".	Handling (Psychology),Handling, Psychology,Psychological Handling,Psychology Handling
D000222	Adaptation, Physiological	The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.	Adaptation, Physiologic,Adaptations, Physiologic,Adaptations, Physiological,Adaptive Plasticity,Phenotypic Plasticity,Physiological Adaptation,Physiologic Adaptation,Physiologic Adaptations,Physiological Adaptations,Plasticity, Adaptive,Plasticity, Phenotypic
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
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