1169
However, B4-2 has an unusually high proline content (13%), contains a putative nuclear targeting sequence , and has several SPXX motifs which are frequently found in gene regulatory proteins .
 protein: SPXX motifs; protein: nuclear targeting sequence; protein: gene regulatory proteins; DNA: B4-2
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: SPXX motifs; protein: nuclear targeting sequence; protein: gene regulatory proteins; DNA: B4-2