Proteomics of extracellular matrix from eIF4E deficient mouse mammary fat pad

It was demonstrated that mice with eIF4E that cannot be activated by phosphorylation (S209A) produced extracellular matrix (ECM) less conducive to breast cancer tumor invasion and metastasis. To examine whether this could in part bedue to differences in the protein composition we analyzed the proteome of soluble and insoluble ECM fractions derived from the mammary fat pad of mice with either WT or constitutively inactivated (S209A or "KI") eIF4E.