Rho Guanine Nucleotide Exchange Factor 12 (ARHGEF12)

The predicted 1,544-amino acid protein, which they called LARG, has strong homology to several members of the family of Rho GEFs, including such oncogenes as DBL (MCF2), VAV1, TIAM, and BCR. Northern blot analysis detected expression of a 10-kb LARG transcript in all human tissues examined, including peripheral blood leukocytes, spleen, prostate, testis, ovary, small intestine, colon, and minimally in thymus.Transcriptional orientation of both genes at 11q23 was found to be from centromere to telomere, consistent with other data that suggested that the MLL/LARG fusion resulted from an interstitial deletion rather than a balanced translocation. LARG did not appear to have any homology with other known MLL partner genes. The authors concluded that LARG is a novel MLL fusion partner in acute myeloid leukemia.