Biomaterial Database

[Characteristics of testosterone-binding cytoplasmic components in the human endometrium and their interaction with chromatin]. 1975

N A Iudaev, and B V Pokrovskiĭ, and M K Asreibekova, and A V Mal'tsev

The existence of macromolecules which specifically bind 3H-testosterone is demonstrated in the soluble fraction of human uterus endometrium. Testosterone receptors of endometrial cytosol are heterogenous and comprise the component with high affinity (Kd--2,9x10(-10) M) and low capacity (concentration of binding sites--0,5 pmoles per mg of protein) and the component with lower affinity and higher capacity (4x10(-9) M and 4 pmoles/mg of protein respectively). Incubation of sliced of endometrium at 37 (but not at 0 degrees) with 3H-testosterone results in the binding of the steroid by chromatin. On the other hand, testosterone-cytoplasmic receptor complex is able to associate with chromatin at 0 degrees. Chromatin did not bind free 3H-testosterone under these conditions. The existence of the receptor for testosterone in endometrial cells promoting its transport into the nucleus and binding with chromatin corroborates the previously shown specific action of testosterone on messenger RNA biogenesis in the uterus. Polyinductor model of regulation of gene expression in higher organisms by steroid hormones is discussed.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D002843	Chromatin	The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.	Chromatins
D003593	Cytoplasm	The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Protoplasm,Cytoplasms,Protoplasms
D004717	Endometrium	The mucous membrane lining of the uterine cavity that is hormonally responsive during the MENSTRUAL CYCLE and PREGNANCY. The endometrium undergoes cyclic changes that characterize MENSTRUATION. After successful FERTILIZATION, it serves to sustain the developing embryo.	Endometria
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining