C190RF5 is a homologue or microtubule-associated protein MAP1B that interacts with natural paclitaxel-like microtubule stabilizer and candidate tumor suppressor RASSF1A. Although normally distributed throughout the cytosol. C190RF5 specifically associates with microtubules stabilized by paclitaxel or RASSF1A. At suffciently high concentrations C190RF5 causes mitochondrial aggregation and genome destruction (MAGD). The accumulation on hyperstabilized microtubules coupled to MAGD has been proposed to mediate tumor suppression by the taxoid drug family and RASSFIA, Here, we show that the C-terminus of C190RF5 (C190RF5C) interacts with mitochondria-associated DNA binding protein, LRPPRC. in liver cells. Like LRPPRC, C190RF5 also binds DNA with an affinity and specificity sufficient to be of utility in DNA affinity chromatography to purify homoogeneous recombinant C190RF5C from bacterial extracts. Homogeneous C190RF5 exhibited no intrinsic DNase activity. Deletion mutagenesis indicated that C190RF5 selectively binds double stranded DNA through its microtubule binding domain, These results suggest C190RF5 as a DNA binding protein similar to microtubule-associated proteins tau and MAP2, (c) 2005 Elsevier Inc. All rights reserved.