The use of alternative polyadenylation sites renders integrin β1 (Itgb1) mRNA isoforms with differential stability during mammary gland development.

Integrins are heterodimeric cell-surface adhesion receptors that play a critical role in tissue development. Characterization of the full-length mRNA encoding the β1 subunit (Itgb1) revealed an alternative functional cleavage and polyadenylation site that yields a new Itgb1 mRNA isoform 578 bp shorter than that previously reported. Using a variety of experimental and bioinformatic approaches, we found that the two Itgb1 isoforms are expressed at different levels in a variety of mouse tissues, including the mammary gland, where they are differentially regulated at successive developmental stages.

BUHO: a MATLAB script for the study of stress granules and processing bodies by high-throughput image analysis.

The spontaneous and reversible formation of foci and filaments that contain proteins involved in different metabolic processes is common in both the nucleus and the cytoplasm. Stress granules (SGs) and processing bodies (PBs) belong to a novel family of cellular structures collectively known as mRNA silencing foci that harbour repressed mRNAs and their associated proteins. SGs and PBs are highly dynamic and they form upon stress and dissolve thus releasing the repressed mRNAs according to changes in cell physiology.

Mammary differentiation induces expression of Tristetraprolin, a tumor suppressor AU-rich mRNA-binding protein.

Tristetraprolin (TTP) is a RNA-binding protein that inhibits the expression of pro-inflammatory cytokines and invasiveness-associated genes. TTP levels are decreased in many different cancer types and it has been proposed that this protein could be used as a prognostic factor in breast cancer. Here, using publicly available DNA microarray datasets, "serial analysis of gene expression" libraries and qRT-PCR analysis, we determined that TTP mRNA is present in normal breast cells and its levels are significantly decreased in all breast cancer subtypes.

Tumor necrosis factor alpha induces LIF expression through ERK1/2 activation in mammary epithelial cells.

It has been reported that expression of tumor necrosis factor superfamily members occur at the onset of the mammary gland post-lactational involution. One of these proteins, tumor necrosis factor alpha (TNFalpha), is a major mediator of inflammation that is able to induce expression of several cytokines. Leukemia inhibitory factor (LIF) is an inflammatory cytokine that is induced and plays a fundamental role during post-lactational involution of the mammary gland.