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Environmental Factor

Environmental Factor

Your Online Source for NIEHS News

May 2019

Korach earns Emeritus Investigator status

Ken Korach, Ph.D., who made pioneering discoveries on estrogen receptor alpha, earned emeritus status from the National Institutes of Health.

Ken Korach, Ph.D., Emeritus Investigator Korach has been an invited speaker at more than 250 national and international meetings and has given more than 30 plenary and keynote lectures. (Photo courtesy of Steve McCaw)

In a rare honor reserved for its most eminent scientists, the National Institutes of Health bestowed the title of Emeritus Investigator on Ken Korach, Ph.D., former head of the Reproductive and Developmental Biology Laboratory. Korach will officially assume the title after his retirement in September.

Korach, whose career has focused almost entirely on understanding the complex molecular behavior of the hormone estrogen, has authored five books, 108 review articles, and more than 390 papers in top-tier journals, including Science, Nature, Proceedings of National Academy of Sciences, and New England Journal of Medicine. His publications have been cited by other scientists in peer-reviewed, published papers more than 39,000 times.

“Korach has distinguished himself and NIEHS with his pioneering work on the molecular mechanisms by which endocrine disruptors affect reproduction and normal physiology,” said NIEHS Scientific Director Darryl Zeldin, M.D. “His findings and generation of novel genetically engineered mouse models have revolutionized the field of reproductive endocrinology.”

Expert in hormones

Korach joined NIEHS in 1976 to head up a lab studying estrogen, a sex hormone involved in female and male reproduction, as well as a variety of other biological processes. His laboratory was the first to generate mice that lacked estrogen receptors, which act as a lock to the hormone’s key, enabling it to exert its action on cells. Korach used these knockout mice to uncover unique roles of estrogen receptors in many diseases and disorders, including infertility, endometriosis, diabetes, and immune and bone diseases.

In a letter of support for his nomination, Benita Katzenellenbogen, Ph.D., from the University of Illinois at Urbana-Champaign, wrote that Korach was an exceptional scientist with a lifetime of contributions to the field. “He is, in my opinion, the leading world expert on the actions of estrogens and estrogen receptors and endocrine disrupting agents in health and disease,” she wrote.

Over the years, Korach and his laboratory have compiled a list of effects of endocrine-disrupting chemicals, which are natural and synthetic compounds named for their ability to mimic estrogen and interfere with the body’s endocrine system. For example, using his mouse models, he showed how diethylstilbestrol, a synthetic estrogen given to pregnant women in the 1940s to prevent miscarriage, worked mechanistically through the estrogen receptor to cause tumors in the reproductive tract and reproductive toxicant effects in the male.

“Throughout his 40-year career at NIEHS, Korach has remained focused on the mission of the institute to understand how the environment impacts human health,” wrote Donald McDonnell, Ph.D., from the Duke University School of Medicine, in his letter of support. “The estrogen receptor is a target of a significant number of environmental toxicants and his work has helped to transform the study of their impact on human disease.”

NIEHS lab members over the years Korach, center, has mentored dozens of lab members over his years at NIEHS. This 2015 photo shows, from left, Lauren Donoghue; Yukitomo Arao, Ph.D.; Sydney Lierz; Tom Neufeld; Sylvia Hewitt; Katherine Hamilton; Yin Li, Ph.D.; Joy Winuthayanon, Ph.D.; and Laurel Coons, Ph.D. Hewitt said they are planning a conference in March 2020 to honor Ken and bring together former lab members and other friends. (Photo courtesy of Steve McCaw)

A wide reach

Korach’s laboratory has trained numerous postdoctoral fellows and students who have gone on to successful careers in academia, government, and industry.

According to Sylvia Hewitt, a senior biologist who has worked for Korach since 1987, his success and the success of his trainees can be attributed largely to his mentorship style. “Korach is the opposite of a micromanager,” she said. “He recruits people who are passionate about the research and are independent. That gives them the opportunity to thrive, and him the opportunity to travel the world, giving talks and forging new collaborations.”

One of his recruits, Katie Burns, Ph.D., now leads a successful lab of her own in the Department of Environmental Health at the University of Cincinnati. Burns said whenever she or one of her lab mates would complain about things being difficult, Korach would quip “All the easy stuff is done.” When things went well, he would ask “Are we famous, yet?” “We all knew he was already famous!” she recalled.

Couse JF, Dixon D, Yates M, Moore AB, Ma L, Maas R, Korach KS. 2001. Estrogen receptor-alpha knockout mice exhibit resistance to the developmental effects of neonatal diethylstilbestrol exposure on the female reproductive tract. Dev Biol. 238(2):224-238.

Couse JF, Hewitt SC, Bunch DO, Sar M, Walker VR, Davis BJ, Korach KS . 1999. Postnatal sex-reversal of the ovaries in mice lacking estrogen receptor alpha and beta. Science 286(5448):2328–2331.

Ignar-Trowbridge DM, Nelson KG, Bidwell MC. Curtis SW, Washburn TF, McLachlan JA, Korach KS. 1992. Coupling of dual signaling pathways: epidermal growth factor action involves the estrogen receptor. Proc Natl Aca Sci U S A 89(10):4658–4662.

Lubahn, DB, Moyer JS, Golding TS, Couse JF, Korach KS, Smithies O. 1993. Alteration of reproductive function but not prenatal sexual development after insertional disruption of the mouse estrogen receptor gene. Proc Natl Aca Sci U S A 90(23):11162–11166.

Smith, EP, Boyd J, Frank GR, Takahashi H, Cohen RM, Specker B, Williams TC, Lubahn DB, Korach KS. 1994. Estrogen resistance caused by a mutation in the estrogen-receptor gene in a man. N Engl J Med 331(16):1056–1061.

Winuthayanon W, Hewitt SC, Orvis GD, Behringer RR, Korach KS. 2010. Uterine epithelial estrogen receptor alpha is dispensable for proliferation but essential for complete biological and biochemical responses. Proc Natl Acad Sci U S A 107(45):19272–19277.

(Marla Broadfoot, Ph.D., is a contract writer for the NIEHS Office of Communications and Public Liaison.)

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