CLONING, STRUCTURE, CELLULAR-LOCALIZATION, AND POSSIBLE FUNCTION OF THE TUMOR-SUPPRESSOR GENE LETHAL(3)MALIGNANT BLOOD NEOPLASM-1 OF DROSOPHILA-MELANOGASTER

The tumor suppressor gene, lethal (3) malignant blood neoplasm-1(+), of Drosophila melanogaster is required for the differentiation of the phagocytic blood-cell type, the plasmatocyte. In the homozygously mutated state it causes the malignant transformation of these blood cells. We present here the cloning, sequencing, structure, and expression of the l(3)mbn-1(+) gene during development. The cloned gene was identified by germ-line transformation, generation of revertants, and the detection of the corresponding mRNA in blood cells and other tissues. Homologies of the G-S-rich C-terminus of the putative MBN(83) protein to human cytokeratins K1, K10, and mouse loricrin were found. The structure and possible function of the wild-type l(3)mbn-1(+) gene are discussed. (C) 1994 Academic Press, Inc.