A few were shown to bind directly with cadherin, such as CSK with VE-cadherin and PTP-1B with E- and N-cadherin others bind one of the catenins (adaptor proteins linking cadherin with actin), such as MET and PTPRF with ОІ-catenin and ROCK1 with p120-catenin some interact with other AJ adaptor proteins, such as PRKCA with vinculin and ROCK1 with Shroom3. Some of these kinases and phosphatases have been localized to AJ by immunofluorescence (e.g., ) and others have been shown to associate with AJ by coimmunoprecipitation (e.g., ), but the exact mechanism of recruitment into AJ of most of them is largely unknown. In the end, we will point out open questions and suggest methods to address them. Next, we will describe the targets of phosphorylation within AJ and by examining the consequences of specific phosphorylation events will show how phosphorylation is involved both in assembly and disassembly of AJ, essentially driving the dynamics of this highly responsive structure. First, we will introduce the enzymes responsible for phosphorylation and dephosphorylation at AJs and discuss how they are recruited into AJ and activated. However, here we will focus on the more direct mechanisms in which AJs are regulated by phosphorylation. In some cases, posttranslational modifications have secondary effects on transcription and/or protein transport. Phosphorylation of tyrosine (Y), serine (S), or threonine (T) residues, the topic of this review, is a rapid and reversible form of regulation affecting the majority of AJ proteins. These modifications include glycosylation, lipidation, ubiquitination, acetylation, proteolysis, and phosphorylation. Finally, a cell can control the activity and interactions of a protein at a given location by posttranslational modifications. In fact, both exocytosis and endocytosis of E-cadherin are tightly controlled and the balance between the two processes has been shown to regulate AJ turnover both in vitro and in vivo. Once a protein is expressed the cell can determine its localization by controlling its transport. Indeed, transcriptional regulation of E-cadherin, notably by the snail transcription factor, plays an important role in the breaking down of AJs accompanying epithelial to mesenchymal transition. First, a cell controls whether proteins are synthesized or not. When considering regulatory mechanisms controlling AJ proteins, we distinguish between three subsequent steps of regulation: synthesis, localization, and activation. Thus, there is great interest in understanding the factors that affect assembly and disassembly of cell-cell adhesion at the molecular level. Defects in the adhesive characteristics of epithelial cells are pathological signs and loss of cell-cell adhesion can generate dedifferentiation and invasiveness of human carcinoma cells. Hence, the ability of cells to regulate their adhesive interactions plays a key role during tissue morphogenesis, repair, and renewal. Дuring the development and lifetime of an organism, cells frequently change shape and position relative to their neighbors. Additionally, AJs are instrumental in setting up and maintaining the apicobasal polarity of epithelial cells, they function as mechanosensors and serve as a nexus for signaling affecting important cell decisions, such as survival and differentiation.

By essentially providing a physical link between the actin cytoskeleton of neighboring cells AJs facilitate the integration of individual cells into a tissue. Adherens junctions (AJs) are cell-cell adhesion sites where calcium-dependent cadherin receptors bind with their extracellular domains to cadherins on opposing cells and with their cytoplasmic tails connect-via adaptors-to filamentous actin.

Pajama sam 1 b junction