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.

[EX Q]:  The fz - 1 and fz - 2 genes are widely expressed in rat tissues with the highest steady - state levels of mRNA in kidney , liver , heart , uterus , and ovary .
[EX A]: fz - 1

[EX Q]:  When a longer - 714 to + 78 fragment of the PBGD promoter is used , the - 70 GATA mutant still displays erythroid - specific activity and is cis - activated by the 5 ' HS - 2 enhancer , while the - 100 CCACC mutant is completely inactive in the absence or in the presence of the 5 ' HS - 2 enhancer .
[EX A]: PBGD promoter

[EX Q]:  To clarify the difference , both the Crk II and Crk II - 23 , proteins were expressed in E . coli and examined their binding capacity in vitro .
[EX A]:
Crk II