12371
Its extracellular domain is composed of four cysteine-rich domains , and the cytoplasmic region contains a death domain known to signal apoptosis .
 protein: death domain; protein: cysteine-rich domains; protein: cytoplasmic region
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: death domain, cysteine-rich domains, cytoplasmic region 
Answer:
 protein: death domain; protein: cysteine-rich domains; protein: cytoplasmic region