1239
Both NF-kappa B precursors and I kappa B alpha became strongly phosphorylated with the same kinetics.
 I kappa B alpha, NF-kappa B
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 I kappa B alpha, NF-kappa B