Role of mammary casein kinase in the phosphorylation of milk proteins

1979 ◽  
Vol 46 (2) ◽  
pp. 181-185 ◽  
Author(s):  
Elizabeth W. Bingham

SUMMARYCasein kinase from lactating bovine mammary gland catalyses the transfer of the terminal phosphoryl group of ATP to specific serine residues in dephosphorylated caseins. Best substrates for casein kinase are the dephosphorylated proteins (bovine αs1 - and β-caseins and pepsin), unphosphorylated human β-casein and the dephosphorylated peptide (residues 1–25) from bovine β-casein. Results obtained with bovine and human β-caseins indicate that the two serines underlined in the cluster Ser-Leu-Ser-Ser-Ser are particularly susceptible to the action of casein kinase. Since a similar sequence is found in dephosphorylated αs1-casein, it is probable that serines in this region of αs1-casein are also phosphorylated. The results support the concept that certain serines in casein are particularly susceptible to phosphorylation by casein kinase.

1988 ◽  
Vol 55 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Robert A. Collins ◽  
Keith R. Parsons ◽  
Terry R. Field ◽  
A. John Bramley

SummaryXanthine oxidase (XO) was demonstrated to be present in the teat canal and secretory tissue of the bovine mammary gland by histochemical techniques. Homogenates of these tissues were able to replace XO in an antibacterial assay with Streptococcus uberis. The action of XO on its substrate hypoxanthine was shown to provide an essential component for anti-streptococcal activity mediated by lactoperoxidase. A mechanism is proposed whereby the interaction of XO, lactoperoxidase and thiocyanate may provide antibacterial activity in the teat canal.


2006 ◽  
Vol 40 (4) ◽  
pp. 177-183 ◽  
Author(s):  
Alfonso Zecconi ◽  
Lorenza Cesaris ◽  
Emmanouil Liandris ◽  
Valentina Daprà ◽  
Renata Piccinini

1977 ◽  
Vol 14 (6) ◽  
pp. 618-628 ◽  
Author(s):  
J. C. Anderson ◽  
M. R. Burrows ◽  
A. J. Bramley

The possible role of bacterial adherence in the pathogenesis of experimental mastitis in the mouse was examined with four strains of Escherichia coli. Two of these strains had a known adhesion antigen (K88) and two did not. The K88 antigen did not play a significant role in the virulence or infectivity of E. coli either in the murine or bovine mammary gland. Two E. coli strains, W1 (K88+) and J2 (K88−) were virulent in the mouse but did not adhere to epithelial cells. Both these strains produced clinical mastitis in the cow. A third strain, D282 (K88−), produced mild disease in the mouse but was avirulent in the cow. The fourth strain, 233/1D (K88+), was avirulent in both the mouse and the cow. Strains D282 and 233/1D were killed rapidly by bovine serum whilst J2 and W1 were more resistant. All strains were more sensitive than the control resistant strain E. coli P4, which is known to be highly virulent for the lactating udder.


2011 ◽  
Vol 14 (3) ◽  
pp. 433-442 ◽  
Author(s):  
M. Kozłowski ◽  
J. Wilczak ◽  
T. Motyl ◽  
M. Gajewska

Role of extracellular matrix and prolactin in functional differentiation of bovine BME-UV1 mammary epithelial cells Interactions between extracellular matrix (ECM) and epithelial cells are necessary for proper organisation and function of the epithelium. In the present study we show that bovine mammary epithelial cell line BME-UV1 cultured on ECM components, commercially available as Matrigel™, constitutes a good model for studying mechanisms controlling functional differentiation of the bovine mammary gland. In contact with Matrigel BME-UV1 cells induce apicobasal polarity, and within 16 days form three dimensional (3D) acinar structures with a centrally localized hollow lumen, which structurally resemble mammary alveoli present in the functionally active mammary gland. We have shown that the 3D culture system enables a high expression and proper localisation of integrin receptors and tight junction proteins in BME-UV1 cells to be induced. This effect was not obtained in cells grown in the classical 2D culture system on plastic. Moreover, ECM highly stimulated the synthesis of one of the major milk proteins, β-casein, even in the absence of prolactin. Our results show that contact with ECM plays an important role in the lactogenic activity of bovine MECs, however, prolactin is necessary for the efficient secretion of milk proteins.


2017 ◽  
Vol 55 (3) ◽  
pp. 235 ◽  
Author(s):  
V. S. MAVROGIANNI (Β. Σ. ΜΑΥΡΟΓΙΑΝΝΗ) ◽  
G. C. FTHENAKIS (Γ. Χ. ΦΘΕΝΑΚΗΣ)

In the present article the literature on the defence mechanisms of the bovine mammary gland is reviewed. The article is divided into three sections: (i) The teat, (ii) Cellular defence mechanisms (number of somatic cells, type of somatic cells, counting of somatic cells, defence role of somatic cells: macrophages, neutrophils, lymphocytes) and (iii) Chemoral defence mechanisms (cytokines: IL-1, IL-2, IL-8, granulocyte/macrophage-colony stimulating factor and TNF-a, immunoglobulins, complement, lactoferrin, lactoperoxidase/thiocyanate/ H 2 0 2 system, lysozyme).


2015 ◽  
Vol 16 (2) ◽  
pp. 135-149 ◽  
Author(s):  
Valerie E. Ryman ◽  
Nandakumar Packiriswamy ◽  
Lorraine M. Sordillo

AbstractThe bovine mammary gland is a dynamic and complex organ composed of various cell types that work together for the purpose of milk synthesis and secretion. A layer of endothelial cells establishes the blood–milk barrier, which exists to facilitate the exchange of solutes and macromolecules necessary for optimal milk production. During bacterial challenge, however, endothelial cells divert some of their lactation function to protect the underlying tissue from damage by initiating inflammation. At the onset of inflammation, endothelial cells tightly regulate the movement of plasma components and leukocytes into affected tissue. Unfortunately, endothelial dysfunction as a result of exacerbated or sustained inflammation can negatively affect both barrier integrity and the health of surrounding extravascular tissue. The objective of this review is to highlight the role of endothelial cells in supporting milk production and regulating optimal inflammatory responses. The consequences of endothelial dysfunction and sustained inflammation on milk synthesis and secretion are discussed. Given the important role of endothelial cells in orchestrating the inflammatory response, a better understanding of endothelial function during mastitis may support development of targeted therapies to protect bovine mammary tissue and mammary endothelium.


2011 ◽  
Vol 5 ◽  
pp. BBI.S7003 ◽  
Author(s):  
Massimo Bionaz ◽  
Juan J. Loor

A crucial role for both insulin and mTOR in the regulation of milk protein synthesis is emerging. Bovine mammary biopsies harvested during late-pregnancy through end of subsequent lactation were used to evaluate via quantitative PCR the expression of 44 genes involved in pathways of insulin, mTOR, AMPK, and Jak2-Stat5 signalling and also glucose and amino acid (AA) transporters. We observed an increased expression during lactation of ELF5, AA and glucose transporters, insulin signaling pathway components, MAPK14, FRAP1, EIF4EBP2, GSK3A and TSC1 among mTOR signaling-related genes. Among ribosomal components RPL22 was down-regulated. The overall data support a central role of AA and glucose transporters and insulin signaling through mTOR for the regulation of protein synthesis in bovine mammary gland. Furthermore, the existence of translational competition favoring the translation of milk protein transcripts was inferred from the combined dataset.


Sign in / Sign up

Export Citation Format

Share Document