505
The previously described four sets of 13 - to 18 - base - pair interspersed repeat elements between - 55 and - 580 provide most of the high basal transcriptional strength , whereas the arrangement of further upstream tandemly repeated NF1 - binding sites may contribute significantly to the expanded biological host range for expression of SCMV IE94 compared with HCMV IE68 .
 GENE: NF1 - binding sites; GENE: SCMV IE94; GENE: HCMV IE68
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: NF1 - binding sites; GENE: SCMV IE94; GENE: HCMV IE68