9684
Using an RNase H protection assay and specific blocking oligonucleotides , we find that recognition of the 5 ' splice - site ( 5 ' ss ) and branchpoint sequence ( BPS ) elements by U11 and U12 snRNPs , respectively , displays strong cooperativity , requiring both sites in the pre - mRNA substrate for efficient complex formation .
 RNase H, U11, U12 snRNPs
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 RNase H, U11, U12 snRNPs