Michael Mancini, Ph.D.
Professor, Department of Molecular and Cellular Biology
Director, Integrated Microscopy Core
Baylor College of Medicine
Ph.D., University of Texas Health Science Center at San Antonio
Postdoctoral, University of Texas Institute of Biotechnology
High Throughput Systems Biology of Gene Regulation
In general terms, a highly dynamic and complex set key regulators underly mechanisms of normal and aberrant gene regulation. Over two decades of reductionist biochmical/molecular studies of gene regulation have identified a great wealth of key factors and interactive pathways, often resulting in important transgenic animal models. Consideration of gene regulator mechanisms at the single cell level, however, have been lacking, largely due to technical hurdles. In the past few years, an increasingly powerful series of automated and quantitative imaging capabilities have come to the fore, providing an altogether new ability to generate and mine a wide series of mechanistic data on gene regulation, with the result being an improving cellular appreciation of how gene regulators function. Further, single cell approaches allow a heretofore impossible view of cellular heterogeneity, as numerous measurements can be made on individual cells that are inherently obscured by population analysis, which is typical in biochemical studies. The results from live or fixed cell studies have led to improved appreciation of the importance of spatiotemporal issues of gene regulators and a rethinking of how well classically drawn static diagrams may reflect mechanistic cell biology.
Our laboratory has several single cell-based models of nuclear receptor gene regulation in progress, including estrogen and androgen receptors linked to both mechanistic study of wild type and clinical mutations. We have developed live imaging studies focusing upon intracellular dynamics (time lapse, photobleaching), and high throughput system biology level approaches using state of the art automated fluorescence microscopy and image analyses. Multiplexing of numerous quantitative readouts is an intensive effort, including current single cell analyses that capture hundreds of individual measurements per cell. For example, our current estrogen receptor studies generate quantitative data on NR/CoR trafficking subnuclear organization, promoter occupancy, large scale chromatin modeling, transcription and the cell cycle---all on a per cell basis---and at 384 well plate speed. Single cell-based analyses of both engineered cell lines that allow quantitation of 'visual ChIP' and mRNA synthesis and increasingly, use of highly sensitive/specific mRNA FISH probes to quantify expression of endogenous genes are providing large scale data sets for extensive bioinformatic mining. The goal of these studies is to generalize sophisticated molecular, cytological, functional cellular response fingerprints for normal and mutant receptors and how ligand and RNAi libraries on hand alter these measurements for ultimately predictive personal medicine.
- Bolt, M.J., Stossi, F., Newberg, J.Y., Orjalo, A., Johansson, H.E., and Mancini, M.A. Coactivators enable glucocorticoid receptor recruitment to fine-tune estrogen receptor transcriptional response. Nucleic Acids Res, 41:4036-4048, (2013). PubMed
- Hartig, S.M., He, B., Newbergy, J.Y., Ochsner, S.A., Loose, D.S., Lanz, R.B., McKenna, N.J., Buehrer, B.M., McGuire, S.E., Marcelli, M., and Mancini, M.A. Feed-forward inhibition of androgen receptor activity by glucocorticoid action in human adipocytes. Chemistry and Biology, 19:1126-41, (2012). PubMed
- Ashcroft, F.J., Newberg, J.Y., Jones, E.D., Mikic, I., and Mancine, M.A. High content imaging-based assay to classify estrogen receptor -α ligands based on defined mechanistic outcomes. Gene, 477:42-52, (2011). PubMed
- Szafran, A.T., Sun, H., Hartig, S., Shen, Y., Mediwala, S.N., Bell, J., McPhaul, M.J., Mancini, M.A. and Marcelli, M. Androgen receptor mutations associated with androgen insensitivity syndrome: a high content analysis approach leading to personalized medicine. Adv Exp Med Biol, 707:63-5, (2011). PubMed
- Hartig, S.M., He, B., Long, W., Buehrer, B.M. and Mancini, M.A. Homeostatic levels of SRC-2 and SRC-3 promote early human adipogenesis. J Cell Biol, 192(1):55-67, (2011). PubMed
- Szafran, A.T., Szwarc, M., Marcelli, M., and Macini, M.A. Androgen Receptor Functional Analyses by High Throughput Imaging: Determination of Ligand, Cell Cycle, and Mutation-Specific Effects. PLoS ONE, 3(11):e3605, (2008). PubMed
- Berno, V., Amazit, L., Hinojos, C.A., Zhong, J., Mancini, M.G., and Mancini, M.A. Estrogen receptor -α activated by estradiol or epidermal growth factor induces temporally distinct chromatin remodeling and transcription. PLoS ONE, 3:e2286, (2008).
For more publications, see listing on PubMed.
Department: Department of Molecular and Cellular Biology
Address: Baylor College of Medicine
One Baylor Plaza
Houston, Texas 77030
Additional Links: Molecular and Cellular Biology