9944
Mutagenesis of the CDE / CHR elements and Sp1 sites in this region , alone or in combination , reduced transcriptional activity by 40 - 60 % in asynchronously growing cells and abolished cell cycle periodicity in G2 - M - synchronized cells .
 Sp1 sites
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 Sp1 sites