Identification of 4 novel genes induced in RA-treated NB4 cells. (A) Autoradiogram of 288/JAML, 438, 809, and 813 mRNA expression in NB4 cells either untreated or treated for 24 hours with 5 × 10^-7 M 9-cis RA, and in HT-29 cells as a nonhematopoietic negative control. Positions of the 28S and 18S rRNAs are indicated on the left side. The lower part is methylene blue–stained 28S and 18S rRNAs on membranes after transfer as assessment of RNA quantities in each lane (5 μg total RNA).