Michael Wigler | |
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Born | Michael Howard Wigler September 3, 1947 New York |
Nationality | American |
Alma mater | Princeton University Columbia University (Ph.D.) |
Spouse(s) | Edith |
Children | Benjamin and Joshua |
Scientific career | |
Institutions | Columbia University Cold Spring Harbor Laboratory |
Michael Howard Wigler (born September 3, 1947 in New York) is an American molecular biologist who has directed a laboratory at Cold Spring Harbor Laboratory since 1978 and is a member of the National Academy of Sciences. He is best known for developing methods to genetically engineer animal cells and his contributions to cancer, genomics and autism genetics.
Wigler graduated from Princeton University in 1970, majoring in mathematics, and in 1978 received his PhD from Columbia University in microbiology, and has spent the remainder of his career at Cold Spring Harbor Laboratory (CSHL).
Beginning in the late 1970s, at Columbia University, Wigler, Richard Axel and Saul Silverstein developed methods for engineering animal cells. [1] These methods are the basis for many discoveries in mammalian genetics, and the means for producing protein therapeutics such as those used to treat heart disease, cancer and strokes. [2]
After moving to CSHL, Wigler continued his studies of gene transfer into mammalian cells, exploring the integration of foreign DNA [3] and its stability of expression in host cells, [4] demonstrating the inheritance of DNA methylation patterns, [5] and isolating the first vertebrate genes, [6] and first human oncogenes, [7] using DNA transfer and genetic selection. His laboratory was among the group that first showed the involvement of members of the RAS gene family in human cancer, [8] and that point mutations can activate the oncogenic potential of cellular genes. [9]
Wigler's laboratory was the first to demonstrate that some regulatory pathways have been so conserved in evolution that yeast can be used as a host to study the function of mammalian genes and in particular genes involved in signal transduction pathways and cancer. [10] This led to deep insights into RAS function, eventually solving the RAS biochemical pathway in yeasts and humans, and demonstrating the multifunctional nature of this important oncogene. [11] From this work in fungi new cellular mechanisms were recognized for "insulating" signal transduction pathways with protein scaffolds that reduce cross-talk [12] and for processing and localization of proteins. [13]
During this period Wigler's lab published the first use of epitope tagging for protein purification. [14] Following the success with epitope tagging, Wigler and collaborator Joe Sorge patented methods for the creating libraries of genes encoding diverse families of antibody molecules. [15] The concept of antibody libraries is most often combined with the method of phage display used in development of antibody-based therapeutics.
In the early 1990s, Wigler and collaborator W. Clark Still at Columbia University developed the first method for encoding combinatorial chemical synthesis, a method for using gas chromatography tags to record reaction "history" while building vast libraries of chemical compounds. [16] This approach [17] is still used today for drug discovery.
In this same period, Wigler and Nikolai Lisitsyn developed the concept and applications of representational difference analysis, [18] which led to their identification of new cancer genes, including the tumor suppressor PTEN, [19] and by others the cancer virus-causing Kaposi's sarcoma, KSHV. In the late '90s, Drs. Wigler and Robert Lucito combined genome representations with array hybridization leading to a technique called ROMA [20] used to show common structural variation in genomes. [21]
In the decade since 2004, Wigler and Jim Hicks at CSHL, together with Anders Zetterberg of the Karolinska Institute, applied methods of copy number analysis for prognostication of breast cancer. [22] The need for accurate measurement of nucleic acid molecules led to the development of varietal tags, [23] more commonly known as unique molecular identifiers. This work led to the first successful sequence-based analysis of the genomes of single cancer cells [24] from tumors by Wigler's then-graduate student Nick Navin, and subsequently, tumor cells in circulation by Wigler's collaborator Jim Hicks.
In the early 2000s, Wigler, Jonathan Sebat and Lakshmi Muthuswamy began copy number analysis of healthy individuals, leading to the discovery of a new source of genetic variability, copy number variations or CNVs. [21] The abundance of CNVs in the human genome is a major source of individual variation. The team at CSHL then continued this line of work to demonstrate that spontaneous germ-line mutation is likely to be a major cause for autism. [25] Their observations and theories about autism provide a now widely accepted approach for understanding other human mental and physical abnormalities.
Ras is a family of related proteins which is expressed in all animal cell lineages and organs. All Ras protein family members belong to a class of protein called small GTPase, and are involved in transmitting signals within cells. Ras is the prototypical member of the Ras superfamily of proteins, which are all related in 3D structure and regulate diverse cell behaviours.
The KRAS gene provides instructions for making a protein called K-Ras, part of the RAS/MAPK pathway. The protein relays signals from outside the cell to the cell's nucleus. These signals instruct the cell to grow and divide (proliferate) or to mature and take on specialized functions (differentiate). The K-Ras protein is a GTPase, which means it converts a molecule called GTP into another molecule called GDP. In this way the K-Ras protein acts like a switch that is turned on and off by the GTP and GDP molecules. To transmit signals, it must be turned on by attaching (binding) to a molecule of GTP. The K-Ras protein is turned off (inactivated) when it converts the GTP to GDP. When the protein is bound to GDP, it does not relay signals to the cell's nucleus. It is called KRAS because it was first identified as an oncogene in KirstenRAt Sarcoma virus. The viral oncogene was derived from cellular genome. Thus, KRAS gene in cellular genome is called a proto-oncogene.
NRAS is an enzyme that in humans is encoded by the NRAS gene. It was discovered by a small team of researchers led by Robin Weiss at the Institute of Cancer Research in London. It was the third RAS gene to be discovered, and was named NRAS, for its initial identification in human neuroblastoma cells.
Ras-related C3 botulinum toxin substrate 3 (Rac3) is a G protein that in humans is encoded by the RAC3 gene. It is an important component of intracellular signalling pathways. Rac3 is a member of the Rac subfamily of the Rho family of small G proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases.
Ovarian cancer G-protein coupled receptor 1 is a protein that in humans is encoded by the GPR68 gene.
Ras GTPase-activating protein-binding protein 1 is an enzyme that in humans is encoded by the G3BP1 gene.
Ras-related protein R-Ras2 is a protein that in humans is encoded by the RRAS2 gene.
Ras-related protein Rab-18 is a protein that in humans is encoded by the RAB18 gene.
Ras-related protein Rab-14 is a protein that in humans is encoded by the RAB14 gene.
KIAA1967, also known as Deleted in Breast Cancer 1, is a protein which in humans is encoded by the KIAA1967 gene.
Ras and Rab interactor 1 is a protein that in humans is encoded by the RIN1 gene.
Ras association domain-containing protein 2 is a protein that in humans is encoded by the RASSF2 gene.
Olfactory receptor 2K2 is a protein that in humans is encoded by the OR2K2 gene.
Echinoderm microtubule-associated protein-like 4 is a protein that in humans is encoded by the EML4 gene.
Ras-related protein Rab-25 is a protein that in humans is encoded by the RAB25 gene. It is thought to act as a promoter of tumor development.
Endosialin is a protein that in humans is encoded by the CD248 gene.
Ras-related protein Rab-6C is a protein that in humans is encoded by the RAB6C gene.
T-cell acute lymphocytic leukemia 2, also known as TAL2, is a protein which in humans is encoded by the TAL2 gene.
Centrobin is a protein that in humans is encoded by the CNTROB gene. It is a centriole-associated protein that asymmetrically localizes to the daughter centriole, and is required for centriole duplication and cytokinesis.
Recombinant adeno-associated virus (rAAV) based genome engineering is a genome editing platform centered on the use of recombinant rAAV vectors that enables insertion, deletion or substitiution of DNA sequences into the genomes of live mammalian cells. The technique builds on Mario Capecchi and Oliver Smithies' Nobel Prize–winning discovery that homologous recombination (HR), a natural hi-fidelity DNA repair mechanism, can be harnessed to perform precise genome alterations in mice. rAAV mediated genome-editing improves the efficiency of this technique to permit genome engineering in any pre-established and differentiated human cell line, which, in contrast to mouse ES cells, have low rates of HR.