Biomaterial Database

Changes in the phosphorylation states of connexin43 in myoepithelial cells of lactating rat mammary glands. 1997

I Yamanaka, and A Kuraoka, and T Inai, and T Ishibashi, and Y Shibata

Department of Anatomy, Faculty of Medicine, Kyushu University, Fukuoka/Japan.

Using specific antibodies and cDNA probe, we examined the expression pattern of a major gap junction protein, connexin43 (Cx43), in rat mammary glands during pregnancy and lactation. Double immuno-fluorescence revealed that the labeling of Cx43 was superimposed in the alpha-smooth muscle actin-positive cells, suggesting that myoepithelial cell were interconnected by gap junctions formed of Cx43. Just after delivery, the Cx43-labeled plaques were enlarged and increased in intensity. Northern and Western blot analyses confirmed the dramatic induction of Cx43 at both mRNA and protein levels on the day of parturition. Cx43 mRNA transcript immediately declined, while the increase of Cx43 protein continued for a few days. During pregnancy, immunoblots showed two bands of almost equal amounts at 43 and 45 kDa. Following delivery, the 45-kDa band gradually increased in intensity with a concomitant decrease of the 43-kDa band. From the sixth day of lactation, Cx43 was always detected as a single band at 45 kDa. Alkaline phosphatase treatment of immunoprecipitated Cx43 revealed that both bands represented phosphorylated forms, thus indicating that Cx43 was naturally phosphorylated and that it altered its phosphorylation states during lactation stages. These results suggest that the induction of Cx43 with the changes in the phosphorylation states plays an important role in the lactating function of myoepithelial cells in rat mammary glands. This is the first report on the changes of Cx43 phosphorylation states during physiological stages in vivo.

UI	MeSH Term	Description	Entries
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
D007774	Lactation	The processes of milk secretion by the maternal MAMMARY GLANDS after PARTURITION. The proliferation of the mammary glandular tissue, milk synthesis, and milk expulsion or let down are regulated by the interactions of several hormones including ESTRADIOL; PROGESTERONE; PROLACTIN; and OXYTOCIN.	Lactation, Prolonged,Milk Secretion,Lactations, Prolonged,Milk Secretions,Prolonged Lactation,Prolonged Lactations
D008321	Mammary Glands, Animal	MAMMARY GLANDS in the non-human MAMMALS.	Mammae,Udder,Animal Mammary Glands,Animal Mammary Gland,Mammary Gland, Animal,Udders
D008856	Microscopy, Fluorescence	Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.	Fluorescence Microscopy,Immunofluorescence Microscopy,Microscopy, Immunofluorescence,Fluorescence Microscopies,Immunofluorescence Microscopies,Microscopies, Fluorescence,Microscopies, Immunofluorescence
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D005260	Female		Females
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
D000918	Antibody Specificity	The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.	Antibody Specificities,Specificities, Antibody,Specificity, Antibody