CROP/Luc7A, a novel serine/arginine-rich nuclear protein, isolated from cisplatin-resistant cell line.
A novel putative SR protein, designated cisplatin resistance-associated overexpressed protein (CROP), has been cloned from cisplatin-resistant cell lines by differential display. The N-half of the deduced amino acid sequence of 432 amino acids of CROP contains cysteine/histidine motifs and leucine zipper-like repeats. The C-half consists mostly of charged and polar amino acids: arginine (58 residues or 25%), glutamate (36 residues or 16%), serine (35 residues or 15%), lysine (30 residues, 13%), and aspartate (20 residues or 9%). The C-half is extremely hydrophilic and comprises domains rich in lysine and glutamate residues, rich in alternating arginine and glutamate residues, and rich in arginine and serine residues. The arginine/serine-rich domain is dominated by a series of 8 amino acid imperfect repetitive motif (consensus sequence, Ser-Arg-Ser-Arg-Asp/Glu-Arg-Arg-Arg), which has been found in RNA splicing factors. The RNase protection assay and Western blotting analysis indicate that the expression of CROP is about 2-3-fold higher in mRNA and protein levels in cisplatin-resistant ACHN/CDDP cells than in host ACHN cells. CROP is the human homologue of yeast Luc7p, which is supposed to be involved in 5'-splice site recognition and is essential for vegetative growth.
Nishii
Y
Y
Laboratory of Biochemistry, Division of Applied Life Sciences, Kyoto University Graduate School of Agriculture, Kyoto, Japan.
Morishima
M
M
Kakehi
Y
Y
Umehara
K
K
Kioka
N
N
Terano
Y
Y
Amachi
T
T
Ueda
K
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D002945:Cisplatin / Q000494:pharmacology*; D017931:DNA Primers; D018076:DNA, Complementary; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D017931:DNA Primers; D018076:DNA, Complementary; C404083:LUC7L3 protein, human; D009687:Nuclear Proteins; D012333:RNA, Messenger; D002945:Cisplatin