A cDNA microarray resource enhanced for transcripts specific to the bovine mammary gland (BMAM) has been developed and used in pilot studies to examine gene expression profiles in the mammary gland. One goal driving development of this resource was to shed some light on the pathways and mechanisms specifically related to bovine mammary gland growth and development. To accomplish this, gene expr...

Transforming growth factor-beta (TGF-beta) regulates proliferation, morphogenesis, and functional differentiation in the mammary gland and plays complex roles in mammary tumorigenesis. Here we show that the signaling mediators Smad1-Smad5 are expressed at all stages of mammary gland development. To begin to investigate which Smads mediate which TGF-beta responses, we have analyzed mammary gland...

8 In the mammary gland, vimentin intermediate filaments are expressed in stromal cells and 9 in basal epithelial cell populations including gland-reconstituting mammary stem cells 10 (MaSC), with largely undefined functions. Here, we studied how vimentin deficiency affects 11 mouse mammary gland development. Our results demonstrate that in adult vimentin 12 knockout mice (Vim-/-) mammary ductal...

Even in genomes lacking operons, a gene's position in the genome influences its potential for expression. The mechanisms by which adjacent genes are co-expressed are still not completely understood. Using lactation and the mammary gland as a model system, we explore the hypothesis that chromatin state contributes to the co-regulation of gene neighborhoods. The mammary gland represents a unique ...

The lactating mammary gland is composed of multiple cell types that tightly coordinate the accumulation, production, and secretion of milk components, including essential metals such as zinc (Zn). Our previous studies in animal and cell models implicated the Zn transporter Zip3 (Slc39a3) in mammary gland Zn acquisition. Herein, we investigated this hypothesis directly by utilizing Zip3-null mic...

Disruptions in polarity and mitotic spindle orientation contribute to the progression and evolution of tumorigenesis. However, little is known about the molecular mechanisms regulating these processes in vivo. Here, we demonstrate that Polo-like kinase 2 (Plk2) regulates mitotic spindle orientation in the mammary gland and that this might account for its suggested role as a tumor suppressor. Pl...

Disruptions in polarity and mitotic spindle orientation contribute to the progression and evolution of tumorigenesis. However, little is known about the molecular mechanisms regulating these processes in vivo. Here, we demonstrate that Polo-like kinase 2 (Plk2) regulates mitotic spindle orientation in the mammary gland and that this might account for its suggested role as a tumor suppressor. Pl...

The transplantation of primary mammary epithelial cells after adenovirus-Cre-mediated recombination provides a new approach for the study of specific gene function during mammary gland development and in breast cancer. Most mammary-gland-specific promoters identified to date are regulated by lactogenic hormones. They are expressed predominantly in lobuloalveolar cells during pregnancy and lacta...

Mammary gland development is a complex process that is dependent on interactions between the developing mammary epithelium and the surrounding stromal tissues. We show that mice lacking the triglyceride synthesis enzyme acyl CoA:diacylglycerol transferase 1 (DGAT1) have impaired mammary gland development, characterized by decreased epithelial proliferation and alveolar development, and reduced ...

Sialomucin complex (SMC, Rat Muc4) is a heterodimeric glycoprotein complex consisting of a mucin subunit ASGP-1 (ascites sialoglycoprotein-1) and a transmembrane subunit ASGP-2, which can act as a ligand for the receptor tyrosine kinase ErbB2. SMC is highly expressed on the surface of ascites 13762 rat mammary adenocarcinoma cells, approximately 100 times the level in lactating mammary gland an...