| Popis: |
The ErbB family of receptors are involved in signalling relating to cell proliferation and differentiation through activation of pathways such as PI3K and MAPK. Their overexpression is often found in different cancer types and therefore, their expression is under tight regulation. The ErbB family includes, EGFR, ErbB2, ErbB3, and ErbB4 where all but ErbB3 has a kinase domain, making ErbB3 a pseudokinase. Upon activation of the receptors, they are endocytosed through the formation of a clathrin-coated pit and are degraded in the lysosome. Interestingly, researchers have found that newly synthesised ErbB3 can also be degraded in the proteasome by protein Nrdp1. Suggesting that ErbB3 might work in a ligand-independent manner and needs additional regulatory mechanisms. ACK1 is a non-receptor tyrosine kinase that has a reported effect on EGFR by promoting receptor degradation in the autophagosome. However, their role in EGFR regulation is still debated. Therefore, this information alludes to the fact that ACK1 might influence other ErbB family members as well. This report aims to investigate whether ACK1 influences ErbB3 levels. Through RNAi mediated knockdown of ACK1 in MCF10A cells, a novel role of ACK1 acting as a regulator of ErbB3 is hinted at. Surprisingly, these results also show that ACK1 seems to act specifically on ErbB3 and not on its family members, EGFR and ErbB2. Moreover, this report shows that ErbB3 expression is linked to cell density. |
