9400
Cdk2-dependent phosphorylation therefore provides a switch during late G1-to-S phase that both nullifies an early G1 cell cycle regulatory function of Id3 and modulates its target bHLH specificity .
 bHLH, Id3
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:
 bHLH, Id3