In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

[Q]:  Interaction of cell - type - specific nuclear proteins with immunoglobulin VH promoter region sequences .
[A]: nuclear proteins


[Q]:  The purpose of this study was to evaluate the in vitro activity of the principal metabolites of ATRA [ 4 - hydroxy - retinoic acid ( 4 - OH - RA ) , 18 - hydroxy - retinoic acid ( 18 - OH - RA ) , 4 - oxo - retinoic acid ( 4 - oxo - RA ) , and 5 , 6 - epoxy - retinoic acid ( 5 , 6 - epoxy - RA ) ] in NB4 , a human promyelocytic leukemia cell line that exhibits the APL diagnostic t ( 15 ; 17 ) chromosomal translocation and expresses the PML - RAR alpha fusion protein .
[A]: fusion protein


[Q]:  These findings provide unprecedented experimental evidence that BTK plays a nonredundant and pivotal role in B cell antigen receptor - mediated STAT5A activation in B cells
[A]:
antigen receptor