Iva Greenwald

Last updated

Iva Susan Greenwald
Alma mater MIT
Scientific career
Institutions MRC Laboratory of Molecular Biology
Princeton University
Columbia University
Thesis Genetic studies of muscle structure and cell lineage in Caenorhabditis elegans  (1982)

Iva Susan Greenwald is an American biologist who is Professor of Cell and Molecular Biology at Columbia University. She studies cell-cell interactions and cell fate specification in C. elegans . She is particularly interested in LIN-12/Notch proteins, which is the receptor of one of the major signalling systems that determines the fate of cells.

Contents

Early life and education

Greenwald joined MIT as a graduate student in 1977. [1] She was trained in the classics of molecular biology and developmental genetics. That year, H. Robert Horvitz joined the faculty at MIT, and convinced her to investigate C. elegans . She started working on genetics, functional redundancy cell-lineage mutants. [2] She moved to the MRC Laboratory of Molecular Biology in 1983 [1] where she worked alongside Jonathan Hodgkin, Gary Ruvkun and Victor Ambros, who encouraged her to try to clone LIN-12. [1] It took her two years to develop a strategy to clone LIN-12 (Tc1 transposon tagging), and she identified that that genetic sequence contained epidermal growth factor (EGF) motifs. [3] These investigations were amongst the first to show that worm developmental genes could be cloned, and that aspects of these genes were homologous to human proteins. [3]

Research and career

In 1986, Greenwald joined the faculty at Princeton University. [1] [4] She moved to Columbia University in 1993, and was made professor two years later. [4] Greenwald dedicated her career to understanding the mechanisms that underpin the LIN-12/Notch signalling system. [1] [4] LIN-12/Notch proteins mediate cell-cell interactions. Amongst these processes, Greenwald studies the role of LIN-12/Notich in binary regulation, feedback mechanisms and signal transduction. [1] She has identified new genes that are involved with the modulation of LIN-12/Notch in development and disease.

Awards and honors

Selected publications

Personal life

Greenwald is married to Gary Struhl, with whom she has a daughter. [1]

Related Research Articles

<i>Caenorhabditis elegans</i> free-living species of nematode

Caenorhabditis elegans is a free-living transparent nematode about 1 mm in length that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek caeno- (recent), rhabditis (rod-like) and Latin elegans (elegant). In 1900, Maupas initially named it Rhabditides elegans. Osche placed it in the subgenus Caenorhabditis in 1952, and in 1955, Dougherty raised Caenorhabditis to the status of genus.

H. Robert Horvitz American biologist

Howard Robert Horvitz is an American biologist best known for his research on the nematode worm Caenorhabditis elegans, for which he was awarded the 2002 Nobel Prize in Physiology or Medicine, together with Sydney Brenner and John E. Sulston, whose "seminal discoveries concerning the genetic regulation of organ development and programmed cell death" were "important for medical research and have shed new light on the pathogenesis of many diseases".

Notch signaling pathway

The Notch signaling pathway is a highly conserved cell signaling system present in most animals. Mammals possess four different notch receptors, referred to as NOTCH1, NOTCH2, NOTCH3, and NOTCH4. The notch receptor is a single-pass transmembrane receptor protein. It is a hetero-oligomer composed of a large extracellular portion, which associates in a calcium-dependent, non-covalent interaction with a smaller piece of the notch protein composed of a short extracellular region, a single transmembrane-pass, and a small intracellular region.

WormBook is an open access, comprehensive collection of original, peer-reviewed chapters covering topics related to the biology of the nematode worm Caenorhabditis elegans . WormBook also includes WormMethods, an up-to-date collection of methods and protocols for C. elegans researchers.

An equivalence group is a set of unspecified cells that have the same developmental potential or ability to adopt various fates. Our current understanding suggests that equivalence groups are limited to cells of the same ancestry, also known as sibling cells. Often, cells of an equivalence group adopt different fates from one another.

Presenilin

Presenilins are a family of related multi-pass transmembrane proteins which constitute the catalytic subunits of the gamma-secretase intramembrane protease protein complex. They were first identified in screens for mutations causing early onset forms of familial Alzheimer's disease by Peter St George-Hyslop at the Centre for Research in Neurodegenerative Diseases at the University of Toronto, and now also at the University of Cambridge. Vertebrates have two presenilin genes, called PSEN1 that codes for presenilin 1 (PS-1) and PSEN2 that codes for presenilin 2 (PS-2). Both genes show conservation between species, with little difference between rat and human presenilins. The nematode worm C. elegans has two genes that resemble the presenilins and appear to be functionally similar, sel-12 and hop-1.

Apoptosis is the process of programmed cell death. From its early conceptual beginnings in the 1950s, it has exploded as an area of research within the life sciences community. As well as its implication in many diseases, it is an integral part of biological development.

lin-4 microRNA precursor

In molecular biology lin-4 is a microRNA (miRNA) that was identified from a study of developmental timing in the nematode Caenorhabditis elegans. It was the first to be discovered of the miRNAs, a class of non-coding RNAs involved in gene regulation. miRNAs are transcribed as ~70 nucleotide precursors and subsequently processed by the Dicer enzyme to give a 21 nucleotide product. The extents of the hairpin precursors are not generally known and are estimated based on hairpin prediction. The products are thought to have regulatory roles through complete or partial complementarity to mRNA. The lin-4 gene has been found to lie within a 4.11kb intron of a separate host gene.

The Caenorhabditis eleganssel-12 gene encodes a multi-pass transmembrane domain protein that is similar to human presenilin. sel-12 positively regulates the lin-12 and glp-1 Notch signaling pathways during hermaphrodite gonadal, vulval, and germline development. sel-12 also plays a role in thermotaxis.

Cornelia Bargmann American neurobiologist

Cornelia Isabella "Cori" Bargmann is an American neurobiologist. She is known for her work on the genetic and neural circuit mechanisms of behavior using C. elegans, particularly the mechanisms of olfaction in the worm. She has been elected to the National Academy of Sciences and had been a Howard Hughes Medical Institute investigator at UCSF and then Rockefeller University from 1995 to 2016. Since 2016 she is Head of Science at the Chan Zuckerberg initiative. In 2012 she was awarded the $1 million Kavli Prize, and in 2013 the $3 million Breakthrough Prize in Life Sciences.

Victor Ambros American developmental biologist (born 1953)

Victor R. Ambros is an American developmental biologist who discovered the first known microRNA (miRNA). He is a professor at the University of Massachusetts Medical School in Worcester, Massachusetts.

Gary Bruce Ruvkun is an American molecular biologist at Massachusetts General Hospital and professor of genetics at Harvard Medical School in Boston. Ruvkun discovered the mechanism by which lin-4, the first microRNA (miRNA) discovered by Victor Ambros, regulates the translation of target messenger RNAs via imperfect base-pairing to those targets, and discovered the second miRNA, let-7, and that it is conserved across animal phylogeny, including in humans. These miRNA discoveries revealed a new world of RNA regulation at an unprecedented small size scale, and the mechanism of that regulation. Ruvkun also discovered many features of insulin-like signaling in the regulation of aging and metabolism. He was elected a Member of the American Philosophical Society in 2019.

Notch proteins

Notch proteins are a family of type-1 transmembrane proteins that form a core component of the Notch signaling pathway, which is highly conserved in metazoans. The Notch extracellular domain (NECD) mediates interactions with DSL family ligands, allowing it to participate in juxtacrine signaling. The Notch intracellular domain (NICD) acts as a transcriptional activator when in complex with CSL family transcription factors. Members of this Type 1 transmembrane protein family share several core structures, including an extracellular domain consisting of multiple epidermal growth factor (EGF)-like repeats and an intracellular domain transcriptional activation domain (TAD). Notch family members operate in a variety of different tissues and play a role in a variety of developmental processes by controlling cell fate decisions. Much of what is known about Notch function comes from studies done in Caenorhabditis elegans (C.elegans) and Drosophila melanogaster. Human homologs have also been identified, but details of Notch function and interactions with its ligands are not well known in this context.

Daf-16 Ortholog

DAF-16 is the sole ortholog of the FOXO family of transcription factors in the nematode Caenorhabditis elegans. It is responsible for activating genes involved in longevity, lipogenesis, heat shock survival and oxidative stress responses. It also protects C.elegans during food deprivation, causing it to transform into a hibernation - like state, known as a Dauer. DAF-16 is notable for being the primary transcription factor required for the profound lifespan extension observed upon mutation of the insulin-like receptor DAF-2. The gene has played a large role in research into longevity and the insulin signalling pathway as it is located in C. elegans, a successful ageing model organism.

Shigeo Ohno is a Japanese molecular biologist known for his pioneer research on Protein Kinase C (PKC) and Cell Polarity. His works led to the fundamental understanding of cell polarity in response to cell signaling.

Junying Yuan is the Elizabeth D. Hay Professor of Cell Biology at Harvard Medical School, best known for her work in cell death. Early in her career, she contributed significant findings to the discovery and characterization of apoptosis. More recently, she was responsible for the discovery of the programmed form of necrotic cell death known as necroptosis.

Abby F. Dernburg is a Professor of Cell and Developmental Biology at the University of California, Berkeley, an Investigator of the Howard Hughes Medical Institute, and a Faculty Senior Scientist at Lawrence Berkeley National Laboratory.

Paul W. Sternberg is an American biologist. He does research for WormBase on C. elegans, a model organism.

Gary Struhl is an American research scientist whose primary areas of research are developmental biology and genetics and genomics. He works as a professor at Columbia University Medical Center, teaching neuroscience within the Department of Genetics and Development.

Elizabeth Gavis is an American biologist who is the Damon B. Pfeiffer Professor of Life Sciences, at Princeton University. Davis served as the President of the North American Drosophila Board of Directors in 2011.

References

  1. 1 2 3 4 5 6 7 Greenwald, Iva (July 2012). "Notch and the Awesome Power of Genetics". Genetics. 191 (3): 655–669. doi:10.1534/genetics.112.141812. ISSN   0016-6731. PMC   3389966 . PMID   22785620.
  2. Greenwald, Iva Susan (1982). Genetic studies of muscle structure and cell lineage in Caenorhabditis elegans (Thesis).
  3. 1 2 "lin-12, a nematode homeotic gene, is homologous to a set of mammalian proteins that includes epidermal growth factor". Cell. 43 (3): 583–590. 1985-12-01. doi: 10.1016/0092-8674(85)90230-2 . ISSN   0092-8674.
  4. 1 2 3 4 5 6 7 "Iva S. Greenwald, PhD". Herbert Irving Comprehensive Cancer Center (HICCC) - New York. 2020-09-18. Retrieved 2021-09-04.
  5. "Horvitz Lab Website". web.mit.edu. Retrieved 2021-09-04.
  6. "Iva S. Greenwald". Searle Scholars Program. Retrieved 2021-09-04.
  7. "Iva Greenwald". HHMI. Retrieved 2021-09-04.
  8. "Two Columbia neuroscientists named Howard Hughes investigators". EurekAlert!. Retrieved 2021-09-04.
  9. "Iva S. Greenwald". American Academy of Arts & Sciences. Retrieved 2021-09-04.
  10. "Iva S. Greenwald". www.nasonline.org. Retrieved 2021-09-04.