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.

Tumors binding more than 5 fmol / mg cytosol protein were classified as ER - positive .
cytosol protein

Previously described enhancement of in vitro transcription that was only seen with nuclear extracts derived from B - cell neoplasms corresponding to the late stages of B - cell differentiation was shown to be dependent on the actions of these factor ( s ) on the DNA region within the V kappa gene promoter .
V kappa

Activated PBMCs also expressed lower levels of RXRalpha protein , and a DNA binding assay showed that the activation - induced loss of RXRalpha mRNA and protein expression correlated with the loss of DNA binding activity of this protein .
RXRalpha mRNA