The NER protein Rad33 shows functional homology to human Centrin2 and is involved in modification of Rad4.
In the yeast Saccharomyces cerevisiae the Rad4-Rad23 complex is implicated in the initial damage recognition of the Nucleotide Excision Repair (NER) pathway. NER removes a variety of lesions via two subpathways: Transcription Coupled Repair (TCR) and Global Genome Repair (GGR). We previously showed that the new NER protein Rad33 is involved in both NER subpathways TCR and GGR. In the present study we show UV induced modification of Rad4 that is strongly increased in cells deleted for RAD33. Modification of Rad4 in rad33 cells does not require the incision reaction but is dependent on the TCR factor Rad26. The predicted structure of Rad33 shows resemblance to the Centrin homologue Cdc31. In human cells, Centrin2 binds to XPC and is involved in NER. We demonstrate that Rad4 binds Rad33 directly and via the same conserved amino acids required for the interaction of XPC with Centrin2. Disruption of the Rad4-Rad33 interaction is sufficient to enhance the modification of Rad4 and results in a repair defect similar to that of a rad33 mutant. The current study suggests that the role of Rad33 in the Rad4-Rad23 complex might have parallels with the role of Centrin2 in the XPC-HHR23B complex.
den Dulk
Ben
B
MGC Department of Molecular Genetics, Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
van Eijk
Patrick
P
de Ruijter
Martina
M
Brandsma
Jourica A
JA
Brouwer
Jaap
J
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques; D014466:Ultraviolet Rays
C472752:CETN2 protein, human; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C513460:Rad33 protein, S cerevisiae; C493797:Rad4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins