Signaling pathways, influence

Kundu, A. K., BChatiwala, C. B., and Putnam, A. J. 2008. Extracellular matrix remodeUng, integrin expression, and downstream signaling pathways influence the osteogenic differentiation of mesenchymal stem cells on poly(lactide-co-glycoUde) substrates. Tissue Eng Part A, 15,273-283. 

Adaptor proteins are multi-domain proteins (Fig. 1) that interact with components of signaling pathways [1]. As a consequence of these interactions, adaptor proteins are able to regulate signaling events within the cell, providing spatiotemporal control and specificity, and influencing how a cell responds to a particular stimulus. 

While multiple signaling pathways are implicated in mediating the proliferative effects of CXCL12, only Akt activation, p38 activation, and suppression of cAMP levels have been shown to influence the survival response. Vlahakis et al. (2002) demonstrated that CXCL12 regulates survival in CD4-t T lymphocytes via the balance of pro-survival Akt activation and pro-apoptotic p38 activation. Whether the cellular response to CXCL12 was survival or apoptosis depended on coincident activation of these pathways by other factors. 

In addition to its influence on protein—protein interactions, phosphorylation also affects protein structure and activity. One case involves a protein termed dematin headpiece (DHP), an actin-binding protein found in a variety of tissues including heart, brain, skeletal muscle, kidney, and lung." DHP is known to interact with Ras-guanine nucleotide exchange factor (Ras-GRF2) and this interaction can modulate MARK pathways, which can link the cytoskeleton and signaling pathways." ... 

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