CueK

cueK is a gene found in various bacterial species, most notably in Escherichia coli. It encodes a protein that is a component of the bacterial CUE (Coupling Ubiquitin Entry) system. This system plays a critical role in cellular processes related to protein quality control and degradation.

The protein product of cueK is involved in the ubiquitination pathway. Ubiquitination is a post-translational modification where ubiquitin, a small protein, is attached to a target protein. This attachment can signal the protein for degradation by the proteasome, alter its function, or change its localization within the cell. The CUE system, including the CueK protein, specifically interacts with ubiquitinated proteins, facilitating their recognition and processing.

Specifically, the CueK protein is believed to act as a ubiquitin-binding protein. It recognizes and binds to ubiquitinated substrates, helping to recruit them to degradation machinery or other cellular complexes. This interaction is crucial for clearing damaged or misfolded proteins, thereby maintaining cellular homeostasis. Mutations or disruptions in the cueK gene can lead to defects in protein turnover and potentially impact bacterial survival and virulence. Research into cueK and the CUE system continues to shed light on the intricate mechanisms of protein management in bacteria.