Philip Beachy | |
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![]() Beachy at Stanford | |
Born | Philip Arden Beachy October 25, 1958 Red Lake, Ontario, Canada |
Citizenship | American |
Alma mater | |
Known for | Hedgehog signaling pathway [1] |
Awards | NAS Award in Molecular Biology (1998) March of Dimes Prize in Developmental Biology (2008) Keio Medical Science Prize (2011) |
Scientific career | |
Fields | Biochemistry, Developmental & Stem Cell Biology |
Institutions | |
Thesis | The UBX Domain in the Bithorax Complex of Drosophila (1986) |
Doctoral advisor | David Hogness [2] |
Notable students | Michelle Monje |
Website |
Philip Arden Beachy (born October 25, 1958) [3] is Ernest and Amelia Gallo Professor at Stanford University School of Medicine. [2] [4] Beachy isolated the Hedgehog gene in flies, discovered how it is processed and released from cells, and identified its signaling mechanism in target cells. [5] [6] [7] [8] [9] [6]
He also studied the roles of Hedgehog signaling in development, regeneration and cancer, [10] [11] [12] discovered small molecules that could block the Hedgehog pathway, and advanced them toward patient treatments. [13]
Beachy has received numerous awards and prizes for his work, including the
Beachy was elected a member of the United States National Academy of Sciences in 2002, and a Fellow of the American Academy of Arts and Sciences (2003). [15]
Philip Beachy made several contributions to the understanding of the Hedgehog signaling pathway; he discovered the Hedgehog signaling protein, how it is processed and released from cells, and identified its mechanism of signaling in target cells. [6] [7] [8] [9] [6] [5] Additionally, Beachy revealed critical roles of Hedgehog signaling in embryonic development, [16] uncovering the basis of human birth defects, including holoprosencephaly, the most common human birth defect in early gestation, affecting ~1 in 200 fetuses. He established the concept that morphogens, such as the Hedgehog protein, form extracellular signaling gradients to pattern embryonic tissues, [10] and demonstrated the continued importance of Hedgehog signaling in the maintenance and regeneration of adult organs. [11] [12] Beachy also pioneered small molecule Hedgehog pathway inhibitors, leading to FDA approval of three such inhibitors (vismodegib, sonidegib, and glasdegib) for the treatment of basal cell carcinoma and chronic myelogenous leukemia.
Hedgehog signaling was unknown when Beachy began his work in the early 1990s. Nüsslein-Volhard's and Wieschaus's seminal 1980 study showed that hedgehog mutations cause unusual bristle patterns in Drosophila embryos. Beachy isolated the Drosophila hedgehog gene and revealed that it encodes a secreted signaling protein, thus launching the field of Hedgehog signaling. [5]
Beachy also identified Hedgehog genes critical for the embryonic development of vertebrates, including mammals. He found, surprisingly, that during its production and release the Hedgehog protein autocatalytically cleaves itself and acquires two lipid modifications, cholesterol and palmitate. [8] [17] These lipids render the Hedgehog signal hydrophobic and shape its cellular distribution throughout tissues. These discoveries established covalent lipid modification as a novel mechanism for regulating signaling protein activity; such lipid modification was later extended to Wnt signaling proteins which, like Hedgehog, play important roles in development, regeneration, and cancer.
Beachy also discovered how Hedgehog is released from the cell. The Dispatched protein, powered by Na+ flux through its transmembrane ion channel, extracts the lipid-modified Hedgehog protein from the membrane and releases it as a complex with its carrier Scube, enabling its long-range action as a developmental signal. [18]
After receiving his Ph.D, he worked as an independent fellow (Staff Associate) at the Carnegie Institution's Department of Embryology in Baltimore for two years. He then accepted a faculty position at the Johns Hopkins University School of Medicine and in the Howard Hughes Medical Institute. In 2006, Beachy moved from Johns Hopkins to Stanford University School of Medicine, where he has been affiliated with the Institute for Stem Cell Biology and Regenerative Medicine and has held appointments in the Departments of Developmental Biology, Biochemistry, and Urology.
Beachy was born in Red Lake, Ontario, Canada, on October 25, 1958. [19] Beachy spent eight of his early years of life in the hills of central Puerto Rico. His father was a pastor of a rural church. He attended a school taught in Spanish during the day and then learned to read and write English once he came home from school. At nine, Beachy and his family returned to their home base of Goshen, Indiana where he began attending public school. At the early age of 16, Beachy headed off to Goshen College which was very close to home. At this time, Beachy still did not know of his love for science. “Unlike many people who knew they were going to be scientists from a very early age, I didn't decide that I would try to become a scientist until fairly late on in college,” he says. [2]
Beachy received his bachelor's degree in natural sciences at Goshen College. Beachy first envisioned himself as a doctor, but eventually decided to pursue biological research. He became interested in this field after reading a serialized form of Horace Freeland Judson's book, The Eighth Day of Creation in The New Yorker. "Reading those articles got me excited about molecular biology," says Beachy. After graduating, he continued to do more research and took chemistry courses at the nearby South Bend campus of Indiana University. He then decided to attend graduate school at Stanford University and studied the molecular genetics of fruit fly development with David Hogness. [2] [4] Beachy earned his Ph.D in biochemistry in 1986 at Stanford for research into the Ultrabithorax homeotic gene and its products.
Beachy is married to Katrin Andreasson [20] and is the brother of historian Robert M. Beachy, and a cousin of biologist Roger N. Beachy and author Stephen Beachy.[ citation needed ]
Sonic hedgehog protein (SHH) is encoded for by the SHH gene. The protein is named after the video game character Sonic the Hedgehog.
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The Hedgehog signaling pathway is a signaling pathway that transmits information to embryonic cells required for proper cell differentiation. Different parts of the embryo have different concentrations of hedgehog signaling proteins. The pathway also has roles in the adult. Diseases associated with the malfunction of this pathway include cancer.
Smoothened is a protein that in humans is encoded by the SMO gene. Smoothened is a Class Frizzled G protein-coupled receptor that is a component of the hedgehog signaling pathway and is conserved from flies to humans. It is the molecular target of the natural teratogen cyclopamine. It also is the target of vismodegib, the first hedgehog pathway inhibitor to be approved by the U.S. Food and Drug Administration (FDA).
Mothers against decapentaplegic homolog 2, also known as SMAD family member 2 or SMAD2, is a protein that in humans is encoded by the SMAD2 gene. MAD homolog 2 belongs to the SMAD, a family of proteins similar to the gene products of the Drosophila gene 'mothers against decapentaplegic' (Mad) and the C. elegans gene Sma. SMAD proteins are signal transducers and transcriptional modulators that mediate multiple signaling pathways.
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