Frida E. Kleiman, Ph.D.
Associate Professor - Biochemistry, Cell Biology, Molecular Biology
office 1407N (tel 212-772-5355), lab 1406N (212-772-5380), dept fax 212-772-5332, email email@example.com,
M.S.:National University of Córdoba, Argentina. Ph.D.: National University of Córdoba, Argentina. Postdoc: Columbia University.
Mammalian cells are known to exhibit a sophisticated and coordinated response to DNA damage. We have determined that a dynamic macromolecular assembly of proteins occurs as part of that response and this includes transcription, RNA processing and DNA repair factors. Our lab is interested in identifying and analyzing those protein complexes, to understand the molecular basis of the transcription-coupled repair (TCR) process and how these interactions regulate gene expression after DNA damage. These studies involve a large number of experimental approaches, including a variety of in vitro assays, cell imaging, biochemical fractionation and protein purification, cDNA and genomic DNA cloning, production of recombinant proteins and antibodies, and genetic analyses of cultured cells. Our studies are based on a model whereby the tumor suppressor BRCA1 helps to coordinate a ubiquitous cellular response to DNA damage, a response that includes general factors such as RNA polymerase II (RNAP II) and polyadenylation factors. RNA II is responsible for synthesis of mRNA precursors and also functions directly in TCR process and polyadenylation. Polyadenylation, the addition of the poly(A) tail to an mRNA, is the last step in the synthesis of mRNA and plays important regulatory roles in different cell types and at different stages of the cell cycle. We propose that BRCA1/BARD1-containg complex is recruited to sites of DNA damage, where it functions to initiate degradation of stalled RNAP II, thereby inhibiting the coupled transcription-RNA processing machinery and facilitating repair. Although BRCA1 has been identified as a gene that confers susceptibility to early onset familial breast and ovarian cancers, the determination of a mechanism by which functional loss of BRCA1 promotes tumor formation still constitutes a major challenge. Understanding the role of BRCA1/BARD1 in transcription, RNA processing and DNA repair may contribute not only to improving the therapies and diagnosis of breast cancer, but also, as a long term goal, to developing strategies for the prevention of the disease. We are currently studying how this occurs, and how these interactions contribute to DNA repair and gene control. Current projects in the lab include: 1) Determination of the mechanism(s) of polyadenylation and transcription inhibition by BRCA1/BARD1 after DNA damage. This includes utilization of in vitro assays as well as different in vivo assays for studying different macromolecular assembly formation 2) Analysis of the effect of RNA processing factors on TCR. These studies are being performed in cells deficient in polyadenylation factors. 3) Examination of the intranuclear organization of polyadenylation factors, BARD1, BRCA1 and RNAP II in UV-treated cells. 4) Study of the direct association of BARD1/BRCA1, RNAP II and polyadenylation factors with DNA repair sites.
Kim, H.S., Li, H., Cevher, M., Parmelee, A., Fonseca, D., Kleiman, F.E. and Lee, S.B. (2005). DNA damage-induced BARD1 phosphorylation is critical for the function of BRCA1/BARD1 complex. Submitted.
Kleiman, F.E., Wu-Baer, F., Fonseca, D., Kaneko, S., Baer, R and Manley, J.L. (2005). BRCA1/BARD1 inhibition of 3’ processing involves targeted degradation of RNA polymerase II. Genes Dev. 15(10):1227-37.
Chen, A., Kleiman, F.E., Manley, J.L., Ouchi, T., and Pan, Z.Q. (2002). Auto-ubiquitination of the BRCA1/BARD1 RING ubiquitin ligase. J. Biological Chemistry, 277(24):22085-92.
Kleiman, F.E. and Manley, J.L. (2001). The BARD1-CstF-50 interaction links mRNA 3’ end formation to DNA damage and tumor suppression. Cell, 104:743-753.
Kleiman, F.E. and Manley, J.L. (1999). Functional interaction of BRCA1-associated BARD1 with polyadenylation factor CstF-50. Science, 285:1576-1579.