The contractome – a systems view of actomyosin contractility in non-muscle cells

Abstract

Actomyosin contractility is a highly regulated process that affects many fundamental biological processes in each and every cell in our body. In this Cell Science at a Glance article and the accompanying poster, we mined the literature and databases to map the contractome of non-muscle cells. Actomyosin contractility is involved in at least 49 distinct cellular functions that range from providing cell architecture to signal transduction and nuclear activity. Containing over 100 scaffolding and regulatory proteins, the contractome forms a highly complex network with more than 230 direct interactions between its components, 86 of them involving phosphorylation. Mapping these interactions, we identify the key regulatory pathways involved in the assembly of actomyosin structures and in activating myosin to produce contractile forces within non-muscle cells at the exact time and place necessary for cellular function.

MEKK1-dependent phosphorylation of calponin-3 tunes cell contractility

“…Contractility of non-muscle cells is reportedly modulated by the mechanical properties of the surrounding environments (Geiger et al, 2009;Zaidel-Bar et al, 2015), including the substrate rigidity, as we have observed (Fig. 1C), and as we and others have reported previously (Lo et al, 2000;Paszek et al, 2005;Saez et al, 2005;Yip et al, 2013).…”

Retinoic Acid Receptor‐β Is Downregulated in Hepatocellular Carcinoma and Cirrhosis and Its Expression Inhibits Myosin‐Driven Activation and Durotaxis in Hepatic Stellate Cells

“…It has been observed that tissue tension promotes chronic HSC activation . Thus, we investigated whether RAR‐β activation in HSCs affected the expression of myosin light chain‐2 (MLC‐2), a key regulatory protein in cytoskeletal contractility . Using qPCR, we observed that treatment of HSCs with a RAR‐β agonist (cd2314) for 72 hours induced a significant decrease in MLC‐2 mRNA expression, a reduction also observed with the 10‐day ATRA treatment.…”

“…(6,25) Thus, we investigated whether RAR-β activation in HSCs affected the expression of myosin light chain-2 (MLC-2), a key regulatory protein in cytoskeletal contractility. (26) Using qPCR, we observed that treatment of HSCs with a RAR-β agonist (cd2314) for 72 hours induced a significant decrease in MLC-2 mRNA expression, a reduction also observed with the 10-day ATRA treatment. Combining ATRA treatment with a RAR-β antagonist (cd2665) prevented the effect of ATRA, with control levels of MLC-2 mRNA expression observed ( Fig.…”

The role of apical cell–cell junctions and associated cytoskeleton in mechanotransduction

“…Actin and myosin coat the cytoplasmic faces of the plasma membrane to provide structural rigidity and mechanical resistance to the cell cortex (Heuser and Cooke, 1983;Citi and Kendrick-Jones, 1991;Bretscher et al, 2002). Actomyosin contractility is involved in a large number of cellular functions, besides its involvement at cell-cell junctions, and depends not only on actin and myosin, but also on a variety of regulatory and scaffolding proteins (Zaidel-Bar et al, 2015), which will not be discussed in detail here.…”