The predicted mass of the nucleosome is 262 kD.

TLS Online TPP Program

#Id: 6138

#Unit 3. Fundamental Processes

XP-V is caused by a defect in the translesion DNA polymerase, Pol n. The gene encoding Pol n is sometimes called XPV

TLS Online TPP Program

#Id: 6139

#Unit 3. Fundamental Processes

In global genome repair (GG-NER), the XPC protein detects the damage and initiates the repair pathway. XPC can recognize damage anywhere in the genome. In mammals, XPC is a component of a lesion-sensing complex that also includes the proteins HR23B and centrin2.

TLS Online TPP Program

#Id: 6140

#Unit 3. Fundamental Processes

UV-induced cyclobutane pyrimidine dimers (CPDs), are not well recognized by XPC. In this case, the DNA damage-binding (DDB) complex assists in recruiting XPC to this type of damage.

TLS Online TPP Program

#Id: 6141

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6142

#Unit 3. Fundamental Processes

transcription-coupled repair (TC-NER) TFIIH, itself a large complex, which includes the products of two XP genes, XPB and XPD. 

TLS Online TPP Program

#Id: 6143

#Unit 3. Fundamental Processes

Cleavages are made on either side of the lesion by endonucleases encoded by the XPG and XPF genes. XPG is related to an endonuclease called FEN1 that cleaves DNA during the base excision repair pathway