Identification and functional characterization of the Rad23 gene of the silkworm, Bombyx mori.
Rad23 is an NER (nucleotide excision repair) protein and it plays an important role in the UPP (ubiquitin-proteasome pathway). In the present study, BmRad23 (a homologous gene of Rad23 from Bombyx mori) was cloned and designated as BmRad23. The ORF (open reading frame) of the BmRad23 cDNA encoded deduced 324 amino acids with a calculated molecular mass of 36.13 kDa and an estimated pI of 4.50. The deduced amino acid sequence of the BmRad23 cDNA revealed several indispensable domains for the function of the Rad23 protein family, such as one UbL (ubiquitin-like) region domain and two UBA (ubiquitin-associated) domains. UV irradiation and treatment with chemical DNA-damaging reagent increased the expression of BmRad23. The BmRad23 gene was expressed in all the examined organs, and elevated expression was observed in testis and ovary. Northern blot and immunoblot analyses showed enhanced expression of BmRad23 after day 3 of the wandering stage in the silk gland. From the present results it is suggested that BmRad23 functions in the UPP during the silkworm metamorphosis as well as participating in the NER when the genetic material is damaged by UV irradiation and other genotoxic stresses.
Xu
He-ping
HP
Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou 310029, People's Republic of China.
Xu
Yu-song
YS
Wang
Hua-bing
HB
He
Da
D
Kawasaki
Hideki
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000166:cytology / Q000235:genetics* / Q000378:metabolism*; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D045643:DNA Repair Enzymes / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D006066:Gonads / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification; D008675:Metamorphosis, Biological / Q000235:genetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017434:Protein Structure, Tertiary; D011817:Rabbits; D014466:Ultraviolet Rays / Q000009:adverse effects; D015854:Up-Regulation / Q000502:physiology
D004268:DNA-Binding Proteins; D019476:Insect Proteins; C086985:RAD23A protein, human; D045643:DNA Repair Enzymes