布鲁斯·克努森博士

研究抽象

无花果.1. 核仁的

A century old hallmark of cancer is an enlarged nucleolus (图.1), a unique nuclear sub compartment where RNA polymerase I (Pol I) transcription and ribosome biogenesis take place. Pol I transcription is unregulated in cancer cells and drives cell proliferation, making it an attractive anti-cancer therapeutic target. The major focus of our research is to elucidate the molecular mechanism of Pol I transcription and how its dysregulation leads to cancer and disease. Our research uses an innovative cross-organismal and interdisciplinary approach that integrates 生物信息学, 生物化学, 计算生物学, 遗传学, 蛋白质组学 and structural biology in yeast and human model system.

Molecular architecture of the Pol I preinitiation complex (PIC)

无花果. 2. Pol I PIC模型

Pol I transcription begins with the formation of the PIC (图.2), a macromolecular assemblage of more than 20 different proteins that function coordinately to accurately position Pol I at the promoter and to help initiate transcription. We are interested in the key structural facets of Pol I PIC formation and how it's altered in cancer and diseased cells. Our lab uses an integrated combination of sophisticated protein-protein interaction mapping technologies such as combined chemical 交联/mass spectrometry to determine the spatial orientation of Pol I PIC components and how they change during the transcription cycle and in diseased states.

Pol I与颅面畸形. Mutations in Pol I cause an autosomal dominant craniofacial abnormality called Treacher Collins Syndrome (TCS). TCS is characteried by an underdeveloped lower jaw and cheekbones that is treated by an extensive multi-stage surgical reconstruction from childhood to early adulthood. We are interested in how these Pol I mutations cause TCS, 它们如何影响Pol I活性, and how they can be suppressed to prevent the disease. Currently, there are no known cures for TCS and other related craniofacial dysmorphologies.

无花果.3. Pol规例

Pol I在癌症中的失调. The upregulation of Pol I transcription in cancer cells coincides with activating mutations in many oncogenes and loss of function mutations in tumor suppressors that are believed to directly regulate Pol I activity (图.3). However, their bona fide Pol I targets and sites of interaction remain unclear. To understand how these cancer proteins target the Pol I complex, we use a combination of protein 交联 technologies coupled of 分子遗传学 and 生物化学 to identify and characterize the direct and functionally relevant in vivo Pol I targets. These studies will illuminate new strategies to control aberrant Pol I activity.

克努森实验室的研究生研究. Interested students should directly contact Bruce Knutson to discuss available research opportunities.

克努森巴, McNamar R, Rothblum LI. Dynamics of the RNA polymerase I TFIIF/TFIIE-like subcomplex: a mini-review. 生物化学Soc. 2020年10月30日;48(5):1917-1927. doi: 10.1042 / BST20190848.

克努森巴, Smith ML, Belkevich AE, Fakhouri AM. Molecular 前ology of RNA Polymerase I Upstream Activation Factor. Mol细胞生物学. 2020年6月15日;40(13):e00056-20. doi: 10.1128 / MCB.00056-20. 2020年6月15日.

McNamar R, Abu-Adas Z, Rothblum K, 克努森巴, Rothblum LI. Conditional depletion of the RNA polymerase I subunit PAF53 reveals that it is essential for mitosis and enables identification of functional domains. 生物化学. 2019年12月27日;294(52):19907-19922. doi: 10.1074 / jbc.RA119.009902. Epub 2019 11月

Jackobel AJ, Zeberl BJ, Glover DM, Fakhouri AM, 克努森巴. S. cerevisiae RNA polymerase I Core Factor reveal a preference for the GC-minor groove and a conserved binding mechanism. 生物化学，生物物理，基因调控机制. 2019年9月,1862 (9):194408. doi: 10.1016/j.bbagrm.2019.194408. Epub 2019 8月2日.

Smith ML, Cui W, Jackobel AJ, Walker-Kopp N, Knutson. Reconstitution of RNA Polymerase I Upstream Activating Factor and the Roles of Histones H3 and H4 in Complex Assembly. J摩尔生物学. 2018年Epub

韩勇，何勇，刘建军，刘建军. Breaking the mold: structures of the RNA polymerase I transcription complex reveal a new path for initiation. 转录. 2018年1月15:1-7

Walker-Kopp N, Jackobel AJ, Pannafino GN, Morocho PA, Xu X, 克努森巴. Treacher Collins syndrome mutations in Saccharomyces cerevisiae destabilize RNA polymerase I and III complex integrity. Hum Mol 基因t. 2017年11月1日;26(21):4290-4300.

Han Y, Yan C, Nguyen THD, Jackobel AJ, Ivanov I, 克努森巴, He Y. Structural mechanism of ATP-independent transcription initiation by RNA polymerase I. Elife. 5 . 2017年6月17日.

克努森巴, Smith ML, Walker-Kopp N, Xu X. Super elongation complex contains a TFIIF-related subcomplex. 转录. 2016. 7(4):133-40

克努森巴, Lui J, Ranish J. 哈恩年代. S的体系结构.cerevisiae RNA polymerase I Core Factor complex. 自然、结构与分子生物学. 2014. 21(9): 810-816

克努森巴, 哈恩年代. TFIIB-related factors in RNA polymerase I transcription. 生物化学学报. 2013. 1829(3-4): 265-273

克努森巴. Emergence and expansion of TFIIB-like factors in the plant kingdom. 基因. 2013. 526(1): 30-38

克努森巴, 哈恩年代. Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors. 科学. 2011. 33(6049): 1637-40

克努森巴, 哈恩年代. Domains of Tra1 important for activator recruitment and transcription coactivator functions of SAGA and NuA4 complexes. Mol细胞生物学. 2011. 31(4): 818-831

克努森巴. Insights into the domain and repeat architecture of target of rapamycin. [J]结构生物学. 2010. 170(2): 354-63