CLONING AND CHARACTERIZATION OF TCTA, A GENE LOCATED AT THE SITE OF AT(1-3) TRANSLOCATION

We have cloned and characterized a novel gene at the site of a t(1;3)( p34;p21) translocation breakpoint in T-cell acute lymphoblastic leukem ia. A cDNA for this gene, for which we propose the designation TCTA (T -cell leukemia translocation-associated gene), has been cloned. TCTA m RNA is expressed ubiquitously in normal tissues, with the highest leve ls of expression seen in the kidney. The TCTA gene is conserved throug hout evolution in organisms ranging from Drosophila to humans. A short open reading frame encodes a predicted M(r) 12,000 protein without st rong homology to any previously reported proteins. Of note, genomic So uthern blots demonstrated a reduced TCTA signal in three of four small cell lung cancer cell lines tested, suggesting loss of one of the two copies of the gene.