Cisplatin resistance-associated overexpressed protein (CROP) was originally cloned by differential display from cisplatin-resistant cells. It is an SR-related protein and the human homolog of the yeast protein, Luc7p. Luc7p is an essential protein involved in vegetative growth and 5’-splice recognition. CROP/Luc7a contains arginine- and glutamate-rich domains (RE domains) and arginine- and serine-rich domains (RS domains). It localizes to the nucleus and is distributed as speckles. CROP/Luc7a has been shown to interact with SF2/ASF, a protein involved in RNA splicing. Due to this association and the known function of its yeast homolog, CROP/Luc7a is proposed to play a role in RNA splicing.