Header Logo

Search Result Details

This page shows the details of why an item matched the keywords from your search.
One or more keywords matched the following properties of Nickerson, Jeffrey

Cell and Developmental Biology

Academic Background

Ph.D., 1985, Michigan State University

Nuclear Architecture and Gene Expression

Nucleic acid metabolism is architecturally organized in the eukaryotic nucleus. Nucleic acids themselves- as well as their metabolism in transcription, RNA processing, and RNA export- are structurally constrained to dynamic nuclear domains. Our larger goal is to understand the mechanisms that accomplish the self-assembly of these domains and achieve the spatial organization of gene expression. Our approach is an interdisciplinary one, combining biochemistry and molecular biology with confocal and electron microscopy.

One ongoing project studies the regulation of mRNA export by the PI3 kinase/AKT signal transduction pathway.  Two complexes forming on an mRNA may play a role in its export to the cytoplasm.   The export proteins UAP56, ALY/REF, and NXF1-p15 sequentially bind to a TRanscription/EXport (TREX) complex, located at the 5’ end NXF1 recruited to the complex may subsequently bind at nuclear pores for export of the mRNA to the cytoplasm.   A second complex, the Exon Junction Complex (EJC), with a core of eIF4A3, MLN51, MAGOH, and Y14, forms on the mRNA at sites 24 nucleotides upstream from exon-exon junctions.  We used fluorescence recovery after photobleaching (FRAP) as a live cell screen to find signal transduction pathways that alter the binding of these proteins in mRNA complexes.  Our results show that PI3 kinase/ AKT regulate the binding affinity of UAP56, NXF1, eIF4A3, MAGOH, and Y14 in mRNA-associated complexes in live cells.   In addition, MAGOH binding is strongly reduced by the inhibition of mTORC1.   The active PI3 Kinase/AKT pathway causes increased nuclear retention of a subset of mRNAs in the nucleus, consistent with this signal transduction pathway regulating the export of mRNA.

A second ongoing project, conducted as a long-term collaboration with the laboratory of Tony Imbalzano, also in this department, studies the role of chromatin remodeling in breast cancer.  This project has shown that the SWI/SNF chromatin remodeling enzymes BRG1 and BRM are required for the proliferation of human mammary epithelial cells in conventional tissue culture and in three dimensional reconstituted basement membrane cultures where these cells develop into tissue-like acini.  In addition, reduction in BRG1 levels causes nuclear shape changes that are independent of nuclear-cytoskeletal connections and are mediated by internal nuclear forces.

We have presented evidence that nuclear RNA and the ongoing synthesis of RNA are required for maintaining the normal architecture of the nucleus and have proposed that long non-coding RNAs play this structural role.  A goal for future work is to test this hypothesis and identify specific architectural RNAs in the nucleus.

Director for Cell Biology Confocal Core - Three Dimensional Microscopy - www.umassmed.edu/3dml



Figure: Resinless section of a CaSki cell nuclear matrix. Solubleproteins and chromatin have been removed from this nucleus, uncovering thenuclear matrix which consists of two parts. The nuclear lamina isthe outer shell of the matrix which lies just under the nuclear envelopeand is primarily composed to the lamin proteins A, B, and C. Connected tothe lamina and extending throughout the nuclear volume is the internalnuclear matrix, an intricate structure built on a scaffolding of 10nm filaments whose molecular composition remains unknown. The largest massesremaining in the interior are remnants of nucleoli.

Post Docs


A Postdoctoral Position is available immediately in the Department of Cell and Developmental Biology to study the regulation of RNA processing and export by signal transduction pathways. So far in this project we have found that the assembly of mRNA export complexes in live cells is regulated by the PI3 kinase/AKT signal transduction pathway and that, for a subset of mRNAs, nuclear export is AKT regulated. The experimental approach for this project integrates molecular techniques and microscopy, especially live cell microscopy. The postdoc in this position could also be involved in studies of the role of nuclear architecture in regulating gene expression and in studying the role of chromatin remodeling enzymes in breast cancer.  Candidates with a strong background in cell biology, biochemistry, or molecular biology are especially desirable.

Quaresma, A.J., Sievert, R. & Nickerson, J.A. Regulation of mRNA export by the PI3 kinase/AKT signal transduction pathway. Mol Biol Cell 24, 1208-1221 (2013).

The University of Massachusetts Medical School is located in Worcester, at the western edge of the Boston Metropolitan Area. The Department of Cell and Developmental Biology has especially strong research programs in nuclear and chromatin structure, cytoskeletal function, and mitotic architecture.

Interested candidates should contact:

Jeffrey A. Nickerson, Ph.D.
Department of Cell and Developmental Biology S7-214
University of Massachusetts Medical School
55 Lake Avenue North
Worcester, MA 01655
(508) 856-2312

Rotation Projects

Potential Rotation Projects

     Identify the AKT phosphorylation sites on mRNA export proteins.  Determine the effect that point mutation of those sites has on mRNA export complex assembly and on the export of specific mRNAs.

     Investigate the role of chromatin remodeling in driving the important metabolic changes occurring during breast tumorigenesis.

One or more keywords matched the following items that are connected to Nickerson, Jeffrey
Item TypeName
Academic Article Inducible changes in cell size and attachment area due to expression of a mutant SWI/SNF chromatin remodeling enzyme.
Academic Article Brg1, the ATPase subunit of the SWI/SNF chromatin remodeling complex, is required for myeloid differentiation to granulocytes.
Academic Article Architectural genetic and epigenetic control of regulatory networks: compartmentalizing machinery for transcription and chromatin remodeling in nuclear microenvironments.
Academic Article Nuclear shape changes are induced by knockdown of the SWI/SNF ATPase BRG1 and are independent of cytoskeletal connections.
Academic Article SWI/SNF chromatin remodeling enzyme ATPases promote cell proliferation in normal mammary epithelial cells.
Concept Chromatin Assembly and Disassembly
Academic Article BRG1, a SWI/SNF chromatin remodeling enzyme ATPase, is required for maintenance of nuclear shape and integrity.
Academic Article The SWI/SNF ATPases Are Required for Triple Negative Breast Cancer Cell Proliferation.
Academic Article Targeting the chromatin remodeling enzyme BRG1 increases the efficacy of chemotherapy drugs in breast cancer cells.
Academic Article SMARCA4 regulates gene expression and higher-order chromatin structure in proliferating mammary epithelial cells.
Academic Article The BRG1 chromatin remodeling enzyme links cancer cell metabolism and proliferation.
Academic Article The BRG1 ATPase of human SWI/SNF chromatin remodeling enzymes as a driver of cancer.
Academic Article Nuclear organization mediates cancer-compromised genetic and epigenetic control.
Search Criteria
  • Chromatin Assembly and Disassembly