Multiple interaction partners for Cockayne syndrome proteins: Implications for genome and transcriptome maintenance

• CSA and CSB proteins participate in multiple protein interactions and complexes.
• The CSB protein has functions in BER, TC-NER and transcription.
• The CSB protein is likely to have bifunctional roles in mitochondria.
• The CSA protein is primarily interacting with proteins involved in ubiquitination.

Cockayne syndrome (CS) is characterized by progressive multisystem degeneration and is classified as a segmental premature aging syndrome. The majority of CS cases are caused by defects in the CS complementation group B (CSB) protein and the rest are mainly caused by defects in the CS complementation group A (CSA) protein. Cells from CS patients are sensitive to UV light and a number of other DNA damaging agents including various types of oxidative stress. The cells also display transcription deficiencies, abnormal apoptotic response to DNA damage, and DNA repair deficiencies. Herein we have critically reviewed the current knowledge about known protein interactions of the CS proteins. The review focuses on the participation of the CSB and CSA proteins in many different protein interactions and complexes, and how these interactions inform us about pathways that are defective in the disease.